UNIT 6

The topic about modal to express degrees or certainty was very interesting, because I learned to use modals correctly, when I'm speculating. For example If you want to express speculations or possibilities (50%) about a past situation, you have to use may have/might have and could have + past participle .

Example:
Fact: I was waiting my friend and didn't come.

• She may have forgotten our meeting.
• She might have had an accident.
• She could have gotten lost and arrived when I left.

And also I learned that could have + past participle has two meanings.

Fact: My relatives came here for one week.

• A degree of certainty:
  I could have visited them. (when it's a possibility)
  
• When it's a missed oportunity:
  I could have visited them. (I didn't)

In the negative, use may not have /might not have + past participle

• He may / might not have had enough money to buy that present.

In question, use might have/ could have + past participle

• Might/could she have had enough money?

Saby Chachi-AO4F-Advance Grammar 1