1.варианты ответов:can,can not.
2.варианты ответов:can't,can.
3.варианты ответов:can,can't.​

1. can

2. can't

3. can't

Объяснение:

Can you swim?My sister is ill, so we can't come to the dinner tomorrow night. Sorry.Sally, speak a little louder. We can't hear you at the back of the room.