It usually means a pause after a hint or a hint below or a summary above.
In mathematical language: ① indicates the ratio relationship between them, such as 1: 2, x:y, f (x): g (y); ② Represents the two-point product of two dyadic vectors, such as AB: CD = (A C) (B D).
Basic introduction Chinese name: colon overview: pause after prompt to summarize the above properties: punctuation English version:: definition, function, use, origin, precautions for use, other uses, defining colon as punctuation. It usually means a pause after a hint or a hint below or a summary above. It is written as ":"in English and ":"in Chinese. Divided into Chinese and English half colons and full colons. This function is used after the address to call up the following contents. Comrades, let's have a meeting now. It often appears in letters and official documents. Some people often ignore this colon after the address form, which is easy to write as a comma. The semicolon (1) in Chinese and English is used after the words "say", "think", "yes", "prove", "announce", "for example" and "as follows" to express the following meanings. For example, he was surprised and said, "Ah, it's you!" However, when there are his original words before and after what someone said, then what someone said should be followed by a comma instead of a colon. "This bridge is about to open to traffic," he said, looking around the venue. "Please bite the bullet and make the final sprint." Whether a colon is needed after the words "think", "yes", "prove", "publish", "point out" and "disclose" depends on the situation. For example, (1) factory leaders pointed out in time: "we should strengthen management, grasp the potential of saving, reduce costs through all-round saving, and open up markets with high quality and low cost to increase efficiency." (2) At the meeting, Secretary Li pointed out: "The factory should implement two reform measures, one is to work with certificates, and the other is full-time training." You can't use a colon in the first example, because there is no need to use a colon after "point out". This is a complete sentence without a long pause. If the object part behind is long, you need to make a short pause and only use commas. The second sentence must be a colon, because it leads to the following series of sentences. After the suggestive verbs such as "yes" and "discover", use a colon to lead to the following, and use a period at the end of the following. If you use commas, it is also wrong. For example, there are two poems in * * * ":"Only heroes drive tigers and leopards, and no heroes are afraid of bears ",from which I feel the fearless spirit of * * *. 3. Used after the conclusion words, it indicates that the following arguments are caused. For example, "The Forbidden City in Beijing has four gates: the Wumen Gate, the Shenwumen Gate, the Donghuamen Gate and the Xihuamen Gate." But there are exceptions Don't use a colon if there is no long pause in the sentence. For example, Wang Anyi, Wang Xiaoying and Cheng Naishan, three outstanding women in urban literary circles, were laughing together. Some people will put a colon after "three outstanding women", which is wrong. 4. Used after the words that need to be explained, it means to lead to an explanation or explanation. For example: "Title: Integrity." Motto: not the best, but the closest. 5. Summarize the above contents with the previous general discussion. Example 1: "I can't figure it out, nine cows can't be pulled back; After thinking about it, don't let anyone say it, go straight ahead: he is such a straight temper. " Example 2: If you have a job, do it; If there is a problem, it will light up; If there are shortcomings, correct them: his iron temper is familiar to instructors. Usage 1 After the address used in letters and speeches, it means to mention the following. (1) Mr. Ju Qing: I sent a letter last month, hoping to look around ... ("Wang Guowei to Liu Juqing") (2) Students: On the 20th anniversary of our middle school graduation, someone suggested holding a reunion. (Ren Xiang's speech at the reunion of old classmates) Second, in interviews, debates, symposiums, court hearings and other records, it is used after the name of the speaker. , which leads to the content of the speech. (1) Reporter: You two have been paying attention to Chinese teaching in middle schools. Please talk about how a middle school student learns Chinese well. Qin Mu: To learn Chinese well, we must pay attention to reading, writing and thinking. ..... Zifeng: Besides reading textbooks, you must study after class. ("Qin Mu Wu Zifeng answers a reporter's question") (2) Zheng Fang Jinling: Please don't get me wrong. What I said is not suitable for tourism, not that it is not suitable for developing tourism. Chloe Wang: I don't see any difference between these two questions. ("1986 Asian University Debate Competition Finals") 3. After using suggestive words, it means to mention the following contents. Verbs such as "ask/answer, say, think, yes, just write, think, prove, instruct, point out, for example" can be added with colons to make them suggestive and lead to the object. Q: What do you think is the most important issue in translation? A: As we all know, translation is a report rather than a creation, so the translator: (1) should know what the original author said; Be able to express the original intention accurately in another language. (Wang Zongyan's Distinguishing Meaning as the Basis of Translation) (2) Shakespeare said: "Books are the nourishment of the whole world." (Ye Wenling's My longevity fruit) (3) He thought to himself: This girl is fully qualified to be an excellent singer, but I almost made a mistake! Generally speaking, the most common fault of a work is that there are too many characters and the story is not strong. (Lao She's characters, language and others) (5) I deeply understand that if I hadn't read hundreds of real novels, I would never have written those 800 words. (Ye Wenling's My longevity fruit) [6] It can be seen that this view is that people create the environment and the same environment creates people. (Marx and Engels "Feuerbach") In the example, add a colon after the question/answer, words, thoughts, yes, understanding and instructions. If you don't emphasize the prompt function of these verbs, you can mostly use commas instead of colons. For example, a friend was a little embarrassed to explain that the children were still in school when they bought this big house, and now they are all married. I think this is the true face of the sky. (Sun Sun's Yun Fu) Unfortunately, I have never been to Xiongguan, which is quite close to Beijing. (Jun Qing's Xiongguan Fu) ⑽ I understand why the old people in the town came to sit in the classroom. (Dude's last lesson) ⑾ A lot of facts show that environmental pollution has become a public hazard. (Yu Yongquan's Creating a Good Environment for Humanity-Introduction to Environmental Science) How to use colon and "namely" together needs special explanation. "namely" is equivalent to "just (yes)". Colons can be used after the word "that is" and lead to the following, but not for the word "that is". For example, the quality standards of finished books are divided into two grades, namely, qualified products and unqualified products. (Regulations of the General Administration of Press and Publication on Book Quality Management) 13. This kind of human social activity has a series of unique professional characteristics: universality and particularity, theoretical thinking and artistic behavior. 3. The quality problem of publications is mainly reflected in "three more and one less", that is, there are many mediocre people and few innovators; There are many people patchwork together, but few people are self-contained; There are many people who are shoddy and few people who are elaborate. Use a comma before the word "namely" and a colon after it to introduce the following content. If you don't emphasize the prompt, you can omit the colon after the word "that is". The colon before the word "that is" can be changed to a comma. If the colon is retained, the word "namely" should be deleted, because the colon means to mention the following, and adding "namely" means that the prompt will be repeated. A colon should be added after the word "namely", because the coordinate clauses with semicolons are not separated by colons, and the structural relationship of the whole sentence will be disordered. ⒂ Research topics cover a wide range of fields, such as the nature, characteristics, social functions, editing management, editing team, etc. [14] Ancient poems include many different genres, such as Hunting by Wang Wei and Spring Tour in Qiantang by Bai Juyi, which are well-measured and belong to rhythmic poems; Du Fu's "Li Shihao" has a very wide meter, which is called ancient style (ancient poetry). The usage of "such as" is similar to that of "namely". The colon before the word "Ru" should be changed to a comma. If the colon is retained, the word "Ru" should be deleted. Example [14] has the same problem as [14], and a colon should be added after the word "such as". Fourth, it is used after general discourse to lead to arguments. We usually teach six basic sciences: astronomy, earth science, biology, mathematics, physics and chemistry. (Qian Xuesen's "Basic Science in Modern Natural Science" (2) But generally speaking, good quality cultural products should meet the following standards: politically advanced; High knowledge, academic and artistic; Higher text quality and printing and binding quality; Distinctive characteristics and styles. (Publishing Science 1999/ 1) (3) There are two sources of facts and evidence: one is what I saw with my own eyes, and the other is what I heard from others. (Gu Jiegang's doubts and learning) (4) The examination committee has two opinions on Chen Yiling: one thinks that Chen Yiling's voice is unstable and difficult to create; The other thinks she can try again. (What is a second interview? ) (5) In singing, she [Guo] found her own unique style, that is, the use of (1) breath. With the method of breathing abdomen, the bass is solid, the alto is pure, and the treble is loud and beautiful. (2) accurate articulation and strong penetration. Without a microphone, she can send every word to the last row of the theater. (3) Fashion ... Breathing in frustration, changeable and skilled. (Press and Publication News 1999. 1. 19) Example (1) "Six basic sciences" is the general statement, and the sub-statements are comma-separated juxtaposition words. (2) "Standard" is the total sentence, and the sub-sentence is a parallel phrase separated by semicolons, which can also be changed into commas. (3) "There are two sources" is the general statement, and the sub-statement is a comma-separated parallel clause. Example (4) "Two opinions" are general statements, and the sub-statements are parallel clauses separated by semicolons, because semicolons already contain commas. "Unique" is a group of sentences composed of complex sentences, which are arranged in order to let readers know the scope of each part. Fifth, summarize the above before using it in general discourse. (1) Zhang Hua was admitted to Peking University and studied in the Department of Chemistry; Ping Li entered a secondary technical school, majoring in mechanical manufacturing; I work as a shop assistant in a department store: we all have a bright future. (1996 "Usage of Punctuation") (2) He knows how the dew is sprinkled on the grass and how sweet the dew is; He knows how the stars blink and the moon smiles. He knows how quiet the fields are at night, and how flowers and trees sleep soundly; He knows how bugs look at me, how I look for you, and how butterflies fall in love: in short, he knows everything about the evening. (Ye Shengtao's Scarecrow) (3) It's like a person coming from afar. At first, we only saw whether he was wearing a long coat or a short coat, and then we saw whether he was fat or thin, and then we saw whether he had a square face or a round face. Finally, we saw his eyebrows, even his voice and smile: at this time, we saw everything about him. (On Characters and Structure in Water Margin by Mao Dun) Example (1) "We are All", (2) "All in All" and "All" indicate that the words after the colon are general, and the words before the colon-Shang-are general. 6. After the words that need to be explained, it means that the following is an explanation. (1) The first Guangxi (Guilin) Book Fair will be held grandly. Organizer: Guilin People's Book Fair of Guangxi Press and Publication Bureau Time: 1 9981June15th Book Fair Location: Guilin Gymnasium (press1998.09.29) (1) Life teaches me. (Liu's "Jinghua Tianqiao") (3) Today's sincere person: mail two packages of books and a pile of scattered manuscripts and pray for their preservation. This is a prayer. ("Wang Li vs. Yang Shuda") The colon (1) indicates that the text behind indicates the previous project, and spaces can also be used instead of colons here. The text after the colon explains the previous object "bridge". Example (3) The clause after the colon explains the preceding clause, not the preceding sentence elements. Seven, separate the author and the name of the work. Xu Shen: Interpreting Chinese Characters by Speaking Literatures … (Provisions on the Use of Numbers in Publications) VIII. Separate the subject words in the title from the supplementary explanation. (1) agricultural direction in China: developing ecological agriculture (Xinhua Digest 1996/3) (2) information consumption: new trend of modern society (Guangming Daily 1998.5. 18) (3) Fan Changjiang: the first person to report on the Red Army Long March (Xinhua The form and usage of the colon in the current punctuation marks are imported from the west, while the name is ideographic and original. The word "Mao" means "hidden" and "comprehensive". For example, "provoking" and "taking risks" refer to the beginning or introduction of an article or discourse. Lu Xun's statement in "The Wandering Lonely Man" helps to understand the meaning of the word "Mao". Before and after 19 19, colons used many names: sentence break, colon, quotation marks, set point, set point, narrative point, continuation number, narrative number, knot number, comprehensive number, two points, cool hall, key point, tie point and Karen. Hu Shi once suggested the use of a colon in the form of ":or" in the article On Sentence Reading and Word Count (19 16), and the name used was "Mao". The former is a western-style colon, and the latter is to change two points of the western-style colon into two Chinese-style sharp points. The punctuation marks suggested by Qian in "Sentence Reading Symbols" (19 18) are: "take or knot". The word "knot" obviously refers to summing up the above. The form and name of the colon were formally determined in 19 19's Proposal on Promulgating a New Punctuation Law. Since the end of the 8th century, western religious books, such as the Bible and the Prayer Book, have often used the rising symbol to indicate a big pause in a sentence. This symbol is used when reading scripture prayers or singing hymns. The form of the ascending sign is to add a pick or bean sprout curve to the upper right of the dot, such as (); /kloc-After the middle of the 0/4th century, the symbol added to the dot also evolved into a dot, and the sharp sign became a double dot, which is the predecessor of the colon. The name of the English colon comes from the Greek word k not lon. The word originally meant "limb" (a part of human or animal body) and later became "a part of a poem or sentence". Quintilian, an ancient Roman rhetorician, used the word "Keelung" according to the meaning of "long sentence" in his rhetoric works written in 88 AD. This long sentence symbol was used by Manutius, an Italian publisher in the Renaissance, to mark the pause between a period and a semicolon. There is a comma under the semicolon, because the sentences in early western languages are long, so you need to use (. ) (:) (; ) (,) and other four statements are marked with dots at different structural levels. English is called (:) colon from 1550, which means "long sentence symbol", and the sentence-breaking symbol (; ) Starting from 1644, it is called a semicolon, which means "semi-long sentence symbol". English orthography in the 65438+40s stipulated that comma (,) was the basic unit of pause. ) and (:) indicate that the length of the pause is twice and three times that of the comma, respectively. The documentary evidence of 1748 quoted in the English Oxford Dictionary is: "If we can define a comma as one, a semicolon as two, a colon as three and a period as four". As you can see, colons are used for the first layer of boundaries in sentences, while semicolons are used for the second layer of boundaries. Later, the style of writing gradually changed, and there were more short sentences, so there were not so many symbols indicating grades in sentences. (:) was used for other purposes-from1in the late 8th century, it became a suggestive symbol, which is the origin of modern colon. From this semicolon (; ) becomes the only dot between a period and a comma, and the main function of (:) is no longer to divide long sentences, although some English writers still put a colon before the conjunction and connecting two parallel clauses, which is not universal. From the historical evolution of the etymology and usage of English colons and semicolons, we know that there is no meaningful connection between these two periods in modern times, and semicolons can never be understood as "semicolons". Different from English, French, Italian and Russian are named after Latin in the form of (:), which is called "double dots" (French les deux-points/ Italian due punti/ Russian двоточие). The above French names first appeared in. This period was not introduced into Chinese until the end of 19 and the beginning of the 20th century, so it was translated into "colon" according to its modern meaning, so it cannot be considered that (:) this period has been used as a colon in the west since ancient times. Note that Chinese colons are different from mathematical comparison symbols. The comparison symbol is centered, such as "1:2 = 3: 6"; The colon is located near the lower right corner of the word. Use a colon instead of a tick when separating, for example, "7: 30" should be written as "7:30". Colons in western languages have the same shape as tilde (:), and the distance between two points is slightly wider than that of Chinese colons, and the height is the same as that of ordinary lowercase letters. Note (1) When using a colon, pay attention to its prompt range. The contents of the colon prompt end with a period. If the contents before the period are not all prompted by colons, the use of colons is incorrect. For example, this amazing fact proves that if people always think about money and can't see the enemy's corrosive attacks, they will go astray, which shows that these facts can be used as living teaching materials. The colon in the sentence only means "going astray", not including the back, so it is used wrongly. The comma after "go astray" should be changed to a full stop. Don't use colons unless otherwise specified. He said that he must come to the meeting. The result of the game was unexpected: the old team beat the young team. (The colon should be changed to a comma) (3) In the sentence, the colon cannot be used. The teacher said, "Class dismissed!" And left. You can't use colons in sentences, so you should delete them. (4) Colons are often used after "XXX" and "XXX". But sometimes you don't want to emphasize the prompt, or you don't quote others directly, so you use commas instead of colons. If "so-and-so said" comes after all quotations, use a period after "said". Generally speaking, it is appropriate to have only one colon in a sentence. If a colon is used within the colon range, it constitutes the application of the colon. You should try to avoid using colons. For example, psychological research shows that there are three important factors affecting children's psychological development: heredity, environment and education. (The colon in front should be changed to a comma; Or adjust the word order to "psychological research shows that heredity, environment and education are three important factors affecting children's psychological development." ) other uses in English colons are used to introduce or explain the following, such as this is her plan: to go shopping. Colons are used before lists, especially vertical lists. We transferred three employees to new branches: Tony Wang, new york, Mike Jackson, Tokyo, marc forster and Paris. When the list is horizontal, the colon should be used after the complete sentence. For example, we need seven people: three students, three engineers and a professor. 3. The colon is used before the official quotation. For example, the professor said, "It's terrible. "2. Colons can also be used after the titles of business or formal letters, such as Dear Mr. Li: (In American English, colons are used after the titles of letters or speeches, while commas are often used in British English. ) 6. Colons are used to indicate numerical time, such as 16:45 or 4: 45 pm. Colons are used between main headings and sub-headings. For example, the usage of Web directory: world and non-American economic data in C++ 1 The usage of the single colon (:) (1) indicates the definition of the domain within the institution (that is, how many bit spaces are occupied by the variable) and the typedef struct unsigned char unsigned char (2) structure. The colon after the function plays the role of division. It is a method for class to assign values to member variables and initialize the list, which is more suitable for member variables of constant const type. (3) The colon after public: and private: indicates that all members defined later are public or private before the next "public:" or "private:" appears. Private: "is the default processing. (4) The class name is followed by a colon to define the inheritance of the class. Class Derived Class Name: Inheriting Method Base Class Name The inheritance methods of derived classes are public, private and protected, and the default treatment is public. 2. Usage of double colon (::) ⑴ indicates "domain operator" Example: a class A is declared, and a member function void f () is declared in class A, but the definition of f is not given in the class declaration, so when F is defined outside the class, it should be written as void A::f (), indicating that this f () function is a member function of class A, and it is directly used in front of the global function to indicate that it is global. You can refer to member functions and variables by adding:: (3) before API function names. Examples of scoped member operators: System::Math::Sqrt () are equivalent to System. Math.Sqrt() (4) Usage in batch processing: ":"In batch processing. The label line starts with ":",followed by the identifier. The valid length of the identifier is 8 characters.