Modal Verbs, Can and Could in English
CAN
| ABILITY (Present) | I can speak five languages. |
| POSSIBILITY (Present) | Alcohol can cause cancer. |
| PERMISSION (Informal) | Can I use your computer, please? |
| REQUEST (Informal) | Can you hand me the pen? |
| OFFER (Help) | If they like, I can carry some bags for you. |
COULD
| ABILITY (Past) | He could play football well when he was a kid. |
| POSSIBILITY (Past) | A lot of crime could be prevented. |
| PERMISSION (Polite) | Could I please use your computer? |
| REQUEST (Polite) | Could you tell me where the post office is, please? |
| SUGGESTION | If you want, we could go out for dinner after school? |
