In standard English, two negatives do not make a positive. Instead, they usually reinforce the negative meaning.
Example:
* Incorrect: I don't have no money.
* Correct: I don't have any money.
However, there are some exceptions:
* Double negatives in informal speech: In informal speech, double negatives are sometimes used for emphasis or to create a more colloquial style. However, this is generally considered grammatically incorrect in formal writing.
* Double negatives in certain dialects: Some dialects of English use double negatives as a standard part of their grammar. For example, in some African American Vernacular English (AAVE), double negatives are used to emphasize negation.
In general, it's best to avoid using double negatives in standard English, as they can create confusion and are often considered grammatically incorrect.