Function words are words that have no practical meaning, are dispensable, and have no influence on the meaning of sentences after being removed. For example, the word "er" in "night compose" is a function word, which means "night compose, send out" after being removed, so it is a function word;
As for the analysis and appreciation of sentences, it is to say what benefits some words in sentences have in sentences, what functions they play and what effects they achieve according to the meaning of sentences.
As for sentence punctuation, you should be able to understand sentences without punctuation, and punctuate sentences when necessary. Yes, the meaning of these sentences is very clear. Usually mark a "/"where punctuation is needed in a sentence, indicating that the sentence is not used at the beginning and the sentence is not used at the end. Enter "AAAAAAA" to punctuate the sentence as "AA/AAA/AA".
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