1. He could have given me some advice.

(Does this sentence mean that he didn't give me some advice?)

2. He cold have told a lie.
(Does this sentence mean that he didn't told a lie? Or does #2 mean #3?)

3. He may have told a lie.


English - Writeacher, Tuesday, June 20, 2017 at 7:35am
1. Right, he didn't give advice even though he could have.

2. I'd take this to mean he could have but didn't.

3. This is different. There is doubt whether he told a lie or not.
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Thank you for your help.

4. He might have told a lie.
(What about this one? Is this one similar to #3 or #2?)

4 is similar to 3 above.

4. "He might have told a lie" is similar to sentence #3. It also expresses doubt about whether or not he actually told a lie. It suggests the possibility that he could have lied, but it does not confirm it.