Answer:
would've
should've
could've
might've
Explanation:
The clearly have an 've' at the end. It may be wrong, but there you go. :)
Answer:
I would say that a combination of vivid imagery and a portrayal of things as they really are would be the lessons learned by Hemingway from the paintings of the French post-impressionist Paul Cezanne. Cezanne's portrayal I'm warm colours of people and things makes his images very attractive.
Answer: The student's homework was too difficult to be completed correctly.
Explanation: Lack of apostrophe in students. And randomly adding many didn't make sense to me.