The reason why quotation marks are not used may be that although it is quoted from others, it belongs to "reporting", so quotation marks are not needed.

There are five main uses of quotation marks:

1. Indicating reference.

2, indicating a specific title.

3. express special meaning.

4. Show irony and ridicule.

5. Highlight.

the most basic usage of quotation marks is quotation, which includes direct quotation and indirect quotation.

direct quotation is a complete record of what people say, which can be divided into three situations: the first is the situation that the speaker is in the front and the last, the second is the situation that the speaker is in the middle, and everything he said before and after, and the third is the situation that the speaker is in the back and what he said before.

indirect quotation is a quotation that puts someone's original words in his own words informally, incompletely and with the meaning. If this kind of quotation is not clearly explained, it is difficult to find that it is a quotation.

Extended information:

Notes on quotation:

Quotation refers to quoting others' words in writing. Idioms, aphorisms, poems, etc. also include onomatopoeia and transliteration words. Specific appellations refer to names, abbreviations, special terms and anniversaries with certain characteristics. The words in the special meaning indicator have new meanings in their specific language environment.

when using a quotation, pay attention to the position of punctuation at the end of the quotation. Always use the quoted words independently, and put the dot at the end in quotation marks. If the quoted content is an integral part of a sentence, that is, the quotation has no independence, and there is no need to use a dot at the end of the quoted part (question mark and exclamation mark can be reserved), the whole sentence will pause at this pause, and what dot should be used?

Baidu encyclopedia-quotation marks