Bi Tao, also known as Chiba Peach Blossom, is a variety of peach trees, belonging to semi-double and double ornamental peach varieties, collectively known as Bi Tao. The first time I found this lovely tree species was near a culvert at the end of a group of willows. I didn't notice that this twig was a fruit tree when I passed by here in class before. Occasionally, I noticed a small fruit in the crack of the turquoise twig. Look carefully, there are dozens of sparse above. That little fruit is really pleasing. Its green color is consistent with its peach name, and it also feels a little shy and immature, like a lovely urchin hiding among the green leaves, ashamed to show up, but eager to grow up.
In the later days, I will go every few days to see if these lovely peaches have grown up or been pecked by naughty birds. Over time, these fruits have become a concern in my heart.
Now, summer is coming, and wind, frost, rain and dew are harmoniously mated and woven, which provides a better environment for the growth of peaches. Lovely peach, I look forward to your early growth!
If I were a big tree, I would try my best to help those who need help. ...
If I were a big tree, in the warm spring, I would wake up all my branches and leaves, make my body lush, and make people feel that the cold winter has left and the spring of recovery has arrived. If I grow up in a prosperous city, I will try my best to make this city more dynamic. ...
If I were a big tree, in the hot summer, I would let my body block the strong sunlight and make my body a small piece of cool place. I saw those brothers, sisters, uncles, aunts, grandfathers and grandmothers coming here to enjoy the cool. After a while, two grandfathers came here to play chess; Some grandmothers come here to play mahjong, and some uncles and aunts play cards here. ...
If I were a big tree, I would try my best to make this wasteland scrape less soil in the autumn when the wind is howling. Let those animals shelter from the wind by my side, let them no longer feel the biting autumn wind, and give them a little spiritual warmth. ...
If I were a big tree, in snowy winter, I would let those hibernating animals sleep in my tree hole, make them feel that winter is no longer so cold, and make them feel so warm and comfortable in my hole …
If I can really become a big tree, I will try my best to serve others. No matter how hot, windy and snowy it is, I will try my best to help you. ...
3. Composition about plant explanation methods: two methods, about 600 words, magical plant world.
In the vast world of plants, there is nothing unusual. From the majestic snow-capped mountains to the vast plains, from the plateau with thin air to the boundless ocean, from the desert with changeable wind and sand and drought to the green grassland, from the North Pole to the South Pole of the earth, there are plants everywhere. They are producers of nature, and they are distributed in every corner of the earth. They are particularly magical. They can not only provide us with food, but also provide us with a source of drugs to cure all diseases. Next, let's walk into the magical plant world together.
The simplest plants are algae and bryophytes, which are the basis of the plant kingdom. Cyanobacteria make oxygen for the earth as fast as bacteria. Their footprints are all over the earth, and they can challenge the limits of life. For example, lichens can not die at the high temperature of 70 degrees and the low temperature of-100 degrees, which shows that their adaptability is superior and can last for billions of years. In addition, moss is also a monitor of air quality. Once the air is polluted, they will get sick. Huge kelp, laver and seaweed have become the delicacies of human beings and constitute the bottom of the biological chain on the earth.
After bryophytes, there are ferns. Pteridophyte used to be the master of the earth's plant kingdom, among which the "king of pteridophyte"-Alsophila spinulosa is extremely tall, like a huge green umbrella. Because of its contemporaries with dinosaurs, the existing number is scarce, so it is very precious and is known as a "living fossil". There are about 12000 species of ferns. Due to the influence of Quaternary glaciers, many pteridophytes and dinosaurs also became extinct, while others, such as spiny spiny spiny spiny spiny spiny spiny spiny spiny spiny spiny spiny spiny spiny spiny spiny spiny spiny spiny spiny spiny spiny spiny spiny spiny spiny spiny spiny spiny spiny spiny spiny spiny spiny spiny spiny spiny spiny spiny spiny spiny spiny spiny spiny spiny spiny spiny spiny spiny spiny spiny spiny spiny spiny spiny spiny spiny spiny spiny spiny spiny spiny spiny spiny spiny spiny spiny spiny spiny spiny spiny spiny spiny spin Ferns reproduce in different ways. For example, bamboo shoots will grow and reproduce in spring, spiny ferns and bracken will produce spores for reproduction, and duckweed can reproduce in two ways: asexual and sexual. In ancient times, the abundant reproduction of pteridophytes stored abundant coal resources for human beings. At present, ferns have great economic value and application value in scientific research, ornamental, industry, food, medicine and so on.
The appearance of gymnosperms is a milestone in the evolutionary history of plants. Gymnosperms are seed plants. Due to various reasons, the number of gymnosperms has dropped sharply, leaving only more than 800 species at present. The giant sequoia in the United States is as high as 142 meters, which is a veritable "big MAC" among gymnosperms; "Living fossils"-Metasequoia glyptostroboides, Ginkgo biloba and Metasequoia glyptostroboides are very precious, and they are all national protected plants; Pine trees such as Pinus massoniana continuously flow out rosin, which will form natural amber under suitable geological conditions; Money pine, cedar, Phoebe bournei and Sequoia are called the "five kings" of gymnosperms. In addition, some gymnosperms such as Pinus taiwanensis, Taiwania flousiana, Picea crassifolia, Podocarpus, Acanthopanax argentea and so on are also very rare. Centurium is a strange-looking gymnosperm. It only grows a pair of leaves in its life. It is evergreen all the year round and has huge leaves. Centrium lives as long as centrium, so it is also the longest-lived leaf in the world.
After gymnosperms, angiosperms gradually became the rulers of the earth's plant kingdom. There are about 250 thousand species of angiosperms, which are at the highest level of plant evolution. They range from verdant lawns to156m "the world's tallest plant" eucalyptus apricot, from "big fat tree" to "the world's thickest plant", from 55m-thick Cynanchum paniculatum, from leafless gastrodia elata to leafless flowering crystal orchid. From spinning hemp to cotton, from precious Davidia involucrata, Parthenocissus tricuspidata, ginseng and camellia chrysantha to ironhard ironwood, from the world's largest Kao Hua to the giant konjac with the largest inflorescence, angiosperms abound. Angiosperms are the main source of our food. Many vegetables, such as rice, corn, garlic, beans, Chinese cabbage, Chinese cabbage, except some bracken, algae and fungi, are angiosperms, which are really the granaries of human beings. In addition, there are many angiosperms in Chinese medicine. Among them, ginseng, astragalus, atractylodes macrocephala, aconite, Polygonum multiflorum, atractylodes rhizome, coptis root, etc. They are all good medicines and can cure many diseases. In addition, angiosperms have high ornamental value and can beautify gardens. Angiosperms are the highest level in the plant kingdom.
The plant world is really full of miracles and really interesting. I will study hard and explore the mystery of plants when I grow up.
Growth environment and individual characteristics of plant families
Algae are mostly in water, and there is no differentiation of roots, stems and leaves.
Bryophytes have stems, leaves and rhizomes on the shady wall in wet places, and there is no conducting tissue, so the plants are short.
Pteridophytes have differentiation of roots, stems and leaves in humid environment, and have special conducting tissues. Gymnosperms have seeds, but the seeds are * * *.
Angiosperm seeds are wrapped by seed coat, which can better adapt to the environment.
4. My favorite cactus composition explains 450 words of my favorite cactus in three ways.
Autumn rain, always long and cold, indicates the coming of winter, which is really hard to bear. In the spring rain, I don't know the season, and everything is quiet. If there is no scenery of "blowing open the petals of ten thousand pear trees" in winter snow, it will only bring annoying troubles. It suddenly occurred to me that my cactus is not afraid of this autumn. Even if I don't water for half a month, how can I be afraid of this little autumn rain? It was only that year that it was afraid. Autumn wind brings autumn rain, and the world changes color. Its thin body couldn't support it any longer, and it fell feebly, leaning against the flowerpot, looking like a dying man, struggling to survive. I didn't like its appearance at first, and then I hated it even more. It tries its best to grow into such a strange shape in poor soil. But I don't like it at all. I often don't bother to water it, and even leave it in the corner. Don't you have slender thorns all over this humble plant? What, you want to protect yourself with this? After a long time, I suddenly found that I was no longer decadent and had some vitality. Dark red thorns, slightly larger bodies are a little more green. Even, I drilled a few small cactus balls, tender and green. Newborns generally see the world and are much cuter than their mothers. Soon, cactus balls hung more. "Let's get them down." Mom said. Hearing this, I did nothing but stand on the balcony and enjoy the bright sunshine. I know their mother must be very hard, busy absorbing nutrition and feeding this group of babies lying on her body. Probably a little overwhelmed. But I have other plans. I don't want to disappoint them. After all, it will look better this way. I made a decision that I regret. I know the result. But I still ... look again, there are already more than a dozen cactus balls hanging, one by one, more energetic and more lovely. It's just that their mother is completely exhausted. It never bloomed again. As a flowering cactus, this is a great tragedy. It is dark green, like a layer of ash. It's sick, and it may never get better. It gives all the nutrition to its children, but what about itself? Why doesn't it consider itself? It shouldn't be like this. But how could it give up? One by one is its children, its baby, how can you give up? It's a mother. In this long and cool autumn rain, I think of the great mother, her beauty, her courage, her weakness, her strength, my mother, and all the mothers in the world: they are like spring rain, moistening things silently, and they are still as sad as ever, urging their children's young hearts with endless love.
5. Explanatory text 500 words (six explanations and three explanations) Apple is a kind of fruit that everyone is familiar with. It is chubby and covered with red harvest.
Hold it in your hand and it will gently stick to your palm. When you choose it from thousands of apple trees in Qian Qian, it is a kind of happiness. It can bring sweetness to people, which is its greatest happiness. Apple is a kind of fruit that grows in the north. The idiom "fruitful" refers to it.
Every time you walk through an apple orchard, its attractive fragrance will enter your nostrils and even your whole body with the breeze, and that long-lost comfort will gush out from your long-buried nerves. What could be easier than this? Let me introduce apples! The height of flowering deciduous trees of apple trees can reach 15 meters, and it is generally 3-5 meters high under cultivation conditions.
The trunk is grayish brown, the old bark has irregular longitudinal cracks or flaking, and the branchlets are smooth. The leaf sequence is simple and alternate, oval to ovoid, and the leaf margin is serrated.
Corymb with white petals, pink buds, 20 stamens and 5 styles. Fruit is a kind of kernel, and its color and size vary with varieties.
Apples like light, slightly acidic to neutral soil. It is most suitable for sandy soil with deep soil layer, rich organic matter and good ventilation and drainage of core soil.
There are more than 7500 known species. Improved varieties: "Red Star Series", "Red Fuji" and "Jonathan".
In addition to fresh varieties, there are apples for cooking. Because the fruit acid of apple has the function of retaining water, it is suitable for baking
Apples contain a lot of pectin, which is a soluble fiber that can reduce cholesterol and bad cholesterol. It can also control asthma and chronic obstructive pneumonia.
. Apples have a special effect on enhancing children's memory.
Apple not only contains a variety of vitamins, lipids, minerals, sugars and other essential nutrients for the brain, but also contains fine fibers beneficial to children's growth and development and zinc that can enhance children's memory. Zinc is an essential element that constitutes the nucleic acid and protein closely related to memory. Zinc deficiency will lead to the hypoplasia of hippocampus on the edge of cerebral cortex.
Once zinc in food is reduced, children's memory and learning ability will be seriously damaged, which can last until adulthood. In order to make children have a good memory, children should be allowed to eat more apples.
6. Writing a composition) I grew up in the countryside. There are no bustling streets and the hustle and bustle of the city, but there are fresh and natural scenery and simple and hardworking people.
Tired of hearing the hustle and bustle of the city, please start from me and enjoy the beauty of your hometown! Unconsciously, spring has quietly arrived. The sleeping animals began to wake up, and the grass broke through the ground, sucking up the rain of the earth to the fullest.
The long-frozen river began to melt and make a gurgling sound. Ducks chase each other and play on the water.
Fish jump out of the water from time to time, and flowers are not to be outdone, and they can't wait to open, attracting many "honey collectors". Hard-working people are carrying farm tools in the fields, and lovely swallows are perched on the telephone poles on the roadside, like jumping notes on the staff.
"The next day, the lotus leaf is not beautiful, and the lotus color is different." In a blink of an eye, the hot summer has arrived. The lotus in the pond has filled the river, and naughty dragonflies are flying around among the lotus flowers.
Hard-working people began to transplant rice seedlings. Look, the elderly people are busy walking into the field with a bench in their left hand and a straw in their right hand. They are going to pull out the seedlings.
The young man rolled up his sleeves and bent down to insert some seedlings quickly. The scene of labor is so full of vitality in the sun.
In the silent night, people who worked all day began to fall asleep, and only frogs were heard outside. "Since ancient times, autumn has been sad and lonely. I say spring is better than spring."
Autumn is a season of harvest and joy. The harvester shuttled back and forth in the field, choking from time to time.
The golden ears of rice make a "thump" sound under the breeze. Looking at bags of "fruits of victory", people laughed, and the feeling of relief suddenly drove away all fatigue.
"Like the strong wind in spring, it blows at night and blows open the petals of ten thousand pear trees." Unconsciously, the cold winter has arrived. People gathered around the fire in small groups, talking to each other, talking about this year's harvest, talking about next year's plans, and laughter filled the room.
It snows heavily, and my hometown is like a white velvet coat, pure and beautiful. Look! The children waved happily, made snowmen and had snowball fights. Although the weather is very cold, their hearts are extremely happy! Listen, a string of silvery laughter echoed over the village.
Simple villagers, with big brooms in their hands, cleared the road to provide convenience for passers-by. This is my hometown! It is so natural and simple, I love my hometown.
7. Dashu's self-reported composition 100 words (two interpretations). I am a big tree born in heaven.
I used to be good friends with a lively and lovely bird. She sings sweet songs and dances beautifully every day. As the days passed, the cold winter came, and she would fly to the south for the winter. So I asked her to sing and dance for me next spring. She readily agreed.
A few days after my good friend flew away, one day when I was sleeping, I heard a rustling sound in the Woods, which made my hair stand on end. Suddenly, a man appeared in the grass. He picked up the saw ruler and began to saw me. I was in great pain, paralyzed and fainted. When I woke up, I had been sent to the factory, and vicious humans began to torture me to pieces with machines. I closed my eyes and waited for death … I was made into matches and the workers sold me to a village. At that time, I understood that a match, that is, a little bit in my life, my life has been exhausted. Just then, my good friend Bird flew back. She looked at me and sang last year's song. With tears in my eyes, I really want to say something to my friends, but I can't say it. After she finished singing, she gave me another look and flew away sadly. At the moment I flew to heaven, I thought, "Dear bird, you gave me joy, comfort and sincere friendship ..."
Today, I have become a cadre of the tree of heaven. I also saw that the bird made another good friend. I'm so happy for her. Remember: make friends and keep your word! ! !
8. Explain the composition of plants in five ways. Autumn chrysanthemum will be in late autumn, that is, when chrysanthemum is in full bloom, I will enter the garden again; Go and enjoy the chrysanthemums.
Chrysanthemum is one of the four gentlemen in flowers. It has the beauty of being straight and graceful.
Chrysanthemums bloom in autumn. When the tender leaves of willow turn yellow and other flowers wither, chrysanthemum begins to take root and sprout, and gradually matures. In the wind, in the rain and in the snow, they still stand proudly and grow up gradually.
Chrysanthemums come in many colors, some as big as jade plates, and some as small and exquisite. As for color, red is like fire, white is like snow and yellow is like gold. The stem under the leaves is one foot high, as thick as an adult's finger, and the twigs on the stem are about two inches long. The leaves on the twig are sawed like a small fan, the leaves are green as jade, and the beautiful petals are like a slim girl against the leaves.
Among many chrysanthemums, my favorite is the chrysanthemum called "Fuji Snow Mountain". This is a table chrysanthemum, the petals are slightly rolled in, the petals outside are slightly unfolded, and the whole flower is in a figure, giving you a sense of momentum.
This kind of flower is like a fallen snow mountain, and the leaves set off under it are like an oil-green grassland below. No wonder it's called Mount Fuji Snow Mountain! It's not that chrysanthemums are preferred among flowers.
This ancient poem has been immersed in my heart. I love chrysanthemum, and I love its graceful beauty. Chrysanthemum is the city flower of our city. It will make our city prosperous.
I have an example of writing a composition about plants: plum blossoms have small petals, thin and strong branches, pale pink and fragrant all over. This is a flower that blooms proudly in winter. This is a flower that looks whiter in the snow. It is a flower that cannot be crushed by snowflakes.
Yes, it is plum blossom. Flowers standing proudly in the winter snow.
May, spring and summer seasons. The sun is shining and colorful.
Just after the defeat of Jasminum nudiflorum and Magnolia grandiflora, small buds, strings of pink peach blossoms and lush green grass appeared in the Chinese rose. All this is just as people say, yes, I agree, spring is indeed the season when everything recovers. She gives people the feeling of light green, faint green, endless green, and in summer, the green is deeper, that is green, and the green is deeper.
However, winter, the most lifeless season of the four seasons, gives people the feeling that it is a vast expanse of whiteness, and the snow is overwhelming and sweeping, which can only add a little pine and cypress to this withered winter, and at this time it is covered with thick snow. Those flowers in summer are just dead branches and rotten leaves at this time.
There is no longer the charm, wealth and air of the past, and their only twigs are too tired to breathe under the weight of snow, so they can only wait for death sadly. At this time, in the snow all over the sky, in the lament of everything, plum blossoms appeared and stood proudly in the snow.
Her tall and thin branches are not affected by the snow at all. Snow proud first frost.
In full bloom in the snow, full of pride, standing upright, standing upright, regardless of the wind and snow blowing ... this is why I love plum blossoms, strong and unyielding. Although it is too cold to go out in winter, plum blossoms bloom in the snow. The spirit symbolized by this small flower is far more noble than the colorful roses, Chinese rose and peony in that summer.
Look at that plum blossom. Seemingly pure white snow, only a pool of stains is left after the snow melts, which is flashy. And plum blossom, she is really pure white, sometimes with a little pink, she left a fragrance that seems to be absent. Her simplicity and elegance are beyond the reach of ordinary people.
Look at the plum blossoms standing proudly and blooming in the snow. Don't you feel her beauty at all? Didn't you suddenly see a plum blossom standing in front of you in the vast snow, and you wouldn't be infected by her indomitable spirit of not being afraid of cold and frost? Have you ever thought that she is somewhat similar to the indomitable spirit of the Red Army soldiers? Don't you think this notice covered with heavy snow really symbolizes our revolutionary soldiers, their indomitable spirit, their courage to fight and their will quality? People praise the peony because of its wealth, the lotus because it emerges from the mud without being stained, and I praise the plum because of her indomitable spirit, which also symbolizes those who are more and more brave in the face of difficulties! Nature is beautiful. Lush, evergreen trees and colorful flowers decorate nature and people's lives with their colors, shapes, shapes and functions, creating a beautiful and colorful environment for us and providing all kinds of indispensable resources for mankind. Our survival and life are inseparable from plants, and flowers and trees have become an important theme for students to practice their compositions.
Articles describing plants, whether narrative or expository, are inseparable from "things" and "chanting things". According to Liu Ting, an ancient literary theorist in China, and Wen Xin Diao Long, chanting things and expressing aspirations is called "expressing aspirations according to things". The meaning of this sentence is that Z saw the external things and triggered some ideas, so he expressed his feelings by describing the external things.
For example, Peanut (written by Xu Dishan), Style of Pine Tree (written by Tao Zhu), Camellia Fu (written by Yang Shuo) and Praise of Poplar (written by Mao Dun) that students have learned in Chinese class are all well-known works. So, how to describe plants? First of all, carefully observe and describe the characteristics of plants in detail.
The same flowers, Chunlan, Xiahe, Qiuju and Dongmei, all show their richness. Even the same flower boat has different shapes, colors and smells in different seasons and at different times. It is also green, and there are light green, green and dark green.
It is also fragrant, and it is also divided into fragrance, light fragrance and fragrance. The growth of all kinds of plants has certain rules, generally from germination,-bud, leaf emergence, branch extraction and hole digging to fruiting.
When describing, you should write down the shape characteristics of plants in order. Ye Ding, a student of Shi Jia Hutong Primary School: I wrote an article of several hundred words.
9. Plant composition, with a few explanations 400 words There is a stone in our yard with a little moss on it, which looks like a pile from a distance. There are many trees, thick grass and beautiful flowers in the yard. A cobblestone path winds through the pile, and there is a tall grapefruit tree at the end of the road.
This is a stout grapefruit tree. Surrounded by irregular stones with black and green moss. If you step on it, you will slip. Beside the delicate green grass, beautiful flowers bloom quietly, weaving a bright wreath for the grapefruit tree in the middle. Pomelo trees are so tall, so thick, so thick that even bricks will burst. Unfortunately, there are no insects. Because the trees are too neat!
The most interesting thing is that grapefruit flowers dance and seeds fall to the ground in summer. In autumn, huge Huang Chengcheng grapefruit emerges from the branches. In late autumn, grapefruit grows bigger and bigger. This is our tall, stout, soldier-like grapefruit tree, and this is the grapefruit tree in our yard. Whenever we hit grapefruit with bamboo poles, the yard is full of laughter.
10. Write the characteristics of a thing through explanation. Many people have seen elephants and say they are very big animals.
In fact, there are animals much bigger than elephants, and that is whales. The text introduces whales. Why write about elephants first? Here, the author uses the contrast method of E799Be5BaA6E79Fa5E981933133431346362 to compare unfamiliar things with familiar things, from "very big" elephants to "whales much bigger than elephants", so as to illustrate the whale's.
This article left a vivid impression on people. ② At present, the largest known whale weighs about160,000 kg, and the smallest whale weighs 2,000 kg.
China found a whale weighing nearly 40,000 kilograms, about 17 meters long, with a tongue as heavy as a dozen big fat pigs. If it opens its mouth, people will stand in its mouth. If it raises its hand, it will not touch its upper jaw. Four people will sit around the table and read in its mouth, which is still very spacious.
The author first lists specific figures to illustrate the weight of whales, and uses the weight to illustrate the size of whales. Then, taking a whale found in China as an example, its weight, length and the width of its tongue and mouth vividly show that the whale is really very big.
However, although this whale weighs 40,000 kilograms, it is not the largest. The largest known whale weighs 65438+600,000 kilograms. Through this comparison, it further shows that whales are huge marine animals.
This passage is more accurate and clear through the use of figures and examples, which makes people believe that whales are huge. In ancient times, the ancestors of whales lived on land like the ancestors of cattle and sheep.
Later, the environment changed, and the ancestors of whales lived in the shallow sea near the land. After a long time, their forelimbs and tails gradually become fins, their hind limbs completely degenerate, and their whole bodies become fish-like, adapting to life in the ocean.
This passage mainly talks about the evolution of whales. The appearance of whales has undergone such a great change. The main reason is that the living environment of whales has changed from land to sea. In order to survive, whales have to adapt to the environment, so they slowly change from crawling to swimming, and their bodies gradually become like fish.
This evolution process is very long, and the author uses words such as "in distant ancient times", "very long" and "gradually" to explain it. "Degeneration" means that during the evolution of animals, some organs gradually become smaller, their structures are simplified, their functions decline or even disappear completely.
Here, the whale's hind limbs gradually became smaller during evolution and finally disappeared completely. (4) The nostrils of whales grow on the top of their heads, and when they exhale, they float out of the sea, and the gas emitted from the nostrils forms a water column, just like a fountain in the garden; Wait until your lungs are filled with air, and then dive into the water.
Here, the author uses a vivid metaphor to compare the gas exhaled by whales to a "fountain in the garden". This figurative interpretation method makes the things explained concrete and impressive.
Many people have seen elephants and say that elephants are very big animals. In fact, there are animals much bigger than elephants, and that is whales.
The text introduces whales. Why write about elephants first? Here, the author uses the contrast method of E799Be5BaA6E79Fa5E981933133431346362 to compare unfamiliar things with familiar things, from "very big" elephants to "whales much bigger than elephants", so as to illustrate the whale's. This article left a vivid impression on people.
② At present, the largest known whale weighs about160,000 kg, and the smallest whale weighs 2,000 kg. China found a whale weighing nearly 40,000 kilograms, about 17 meters long, with a tongue as heavy as a dozen big fat pigs.
If it opens its mouth, people will stand in its mouth. If it raises its hand, it will not touch its upper jaw. Four people will sit around the table and read in its mouth, which is still very spacious. The author first lists specific figures to illustrate the weight of whales, and uses the weight to illustrate the size of whales.
Then, taking a whale found in China as an example, its weight, length and the width of its tongue and mouth vividly show that the whale is really very big. However, although this whale weighs 40,000 kilograms, it is not the largest. The largest known whale weighs 65438+600,000 kilograms.
Through this comparison, it further shows that whales are huge marine animals. This passage is more accurate and clear through the use of figures and examples, which makes people believe that whales are huge.
In ancient times, the ancestors of whales lived on land like the ancestors of cattle and sheep. Later, the environment changed, and the ancestors of whales lived in the shallow sea near the land.
After a long time, their forelimbs and tails gradually become fins, their hind limbs completely degenerate, and their whole bodies become fish-like, adapting to life in the ocean. This passage mainly talks about the evolution of whales.
The appearance of whales has undergone such a great change. The main reason is that the living environment of whales has changed from land to sea. In order to survive, whales have to adapt to the environment, so they slowly change from crawling to swimming, and their bodies gradually become like fish. This evolution process is very long, and the author uses words such as "in distant ancient times", "very long" and "gradually" to explain it.
"Degeneration" means that during the evolution of animals, some organs gradually become smaller, their structures are simplified, their functions decline or even disappear completely. Here, the whale's hind limbs gradually became smaller during evolution and finally disappeared completely.
(4) The nostrils of whales grow on the top of their heads, and when they exhale, they float out of the sea, and the gas emitted from the nostrils forms a water column, just like a fountain in the garden; Wait until your lungs are filled with air, and then dive into the water. Here, the author uses a vivid metaphor to compare the gas exhaled by whales to a "fountain in the garden".
This figurative interpretation method makes the things explained concrete and impressive.