Quando usar No ou Not em frases negativas.

Use "not" before a verb or implied verb.

Example:
1.
--Do you understand this question?
--No, I do NOT./ No, I do NOT understand.

2.
-- Who wants ice cream?
--NOT me! (= I do NOT want ice cream)

3.
-- They do NOT speak English.


*Note: When literally followed by a verb, the phrase should be "do not" or "does not" (don't/ doesn't) OR will not (won't), can not (can't), etc.
1. They don't talk. They do not talk.
2. They won't talk. They will not talk.
3. They can't talk. They cannot talk.

You CAN NOT say "They NOT talk." This is incorrect.


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"No" is most often used as a reply/answer or comes before a noun. It is rarely used in a phrase.

Examples:
1.
--Do you speak English?
--No

2.
--No problem.

3.
--I have no money. (BUT it would be better to say "I do not have any money.")

Source: American English
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