Use of Modal Auxiliary Verbs
(1) Used to Express Power, Ability and Capacity.
- He can lift the box.
- He can't speak English.
- I can make jewelry
(2) Used for taking/ giving permission
- You can go now
- can i use your bathroom?
- can i leave now?
(3) Used to make friendly request or suggestion
- Can I take your scooter?
- can i have the bill?
- You can take this spot if you like
(4) Can denotes theoretical possibility.
- Everyone can make a mistake.
(1) Describes an ability, power or capacity that someone had in the past:
- I could swim when I was young.
- You could see the boat sinking.
- I could not come yesterday
(2) Could shows Formal Request
- Could I talk to Mr. Shukla?
- Could you please let me pass you?
- Could I get you more water?
(3) used to express Remote possibility
- There could be a bomb under your seat
- You could always stay at our house
- This plan could really work out