Might, Should, Could and Would in a reported speech!

[Jraou]

Hi
I'd like to know what happens to the following verbs in a reported speech:

Might
Should
Could
Would
Do they change into "Might have p.p.," "Should have p.p.," "Could have p.p.," and "Would have p.p." or do they undergo no changes?

Thanks in Advance

[Mister Micawber]

.
Let's try:

"I might go to Spain next year."
He said that he might go to Spain the next year.

"I should eat my spinach every day."
He said that he should eat his spinach every day.

"If he had been there, I should have seen him!"
She exclaimed that if he had been there, she should have seen him.

"Could you lend me a dollar?"
He asked if I could lend him a dollar.

"They wouldn't come when I asked them to."
He complained that they wouldn't come when he asked them to.

Apparently not.
.
_________________
Native English teacher at Mister Micawber's