1 . Could + Verb base
>> To offer suggestions or possibilities
Example:
A : Oh, no! I left my shorts.
B : Don’t worry 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.