• To offer suggestions or possibilities

Example:
Jason : Oh, no! I left my shorts.
Nate : Don’t worry, Jason. You could borrow my shorts.

Mitchie : I’m having trouble with English.
Demi : Why don’t you ask Tess? Perhaps she could help you.

• To indicate that the ability existed in the past but doesn’t exist now.

Example:
Mitchie : Ras, can you climb the coconut tree?
Shane : Well… I could climb coconut tree when I was so young. But I think I’m too heavy to climb it.

Selena : Grandpa, what could you do when you were younger?
Grandpa : When I was younger, I could swim across the big river very well and faster.

• To express polite requests

Example:
* Could I borrow your pencil (please)?
* Could you lend me your jacket now?
* Could you please close the door?
* Could you pass the salt?

2. Would + Verb base

• For an action that was repeated regularly in the past

Example:
* When I was a child, I would visit my grandparents every weekend.
* On Sundays, when I was a child, we would all get up early and go fishing.

• Insert rather into the pattern and use this expression to express preferences

Example:
Troy : What would you rather do in the weekend, go to the party or stay home?
Ryan : I would rather go to the party than stay home.

Gabriella : Which country would you rather visit?
Sharpay : I would rather visit Italia than Somalia.

• To express polite requests

Example:
Nick : Would you mind cycling with me, Selena?
Selena : No, not at all. It would be nice.

Joey : Would you please pass the helmet, Mary?
Mary : No problem.

3. Should + Verb base

• To give definite advice (advisability)

Example:
Mom : Putri, you should study tonight. You will have English test tomorrow, won’t you?
Mitchie : Joe : You should paint your door, Kevin. It looks terrible.
Kevin : Yes, I know I should.

• To express the subject’s obligation or duty:

Example:
* You should practice for more than an hour. (to musical friend)
* They shouldn’t allow parking here; the street is too narrow.
* Application should be sent before March 25th.

4. Might + Verb base

• To tell possibilities

Example:
Nick : Where is Joe?
Kevin : He might be in the studio with Stella.

•   To express polite requests

Example:
Demi : Might I borrow your coat?
Miley : I’m afraid not. It has been brought by Hannah for weeks and I don’t know when he’ll return it.