Ответ:

1. a) won't be able go

b) should have revised

c) must have been painted

d) need'nt have bought

e) should try

2. a) Students must not be late for lessons.

b) We won't be able to go...

c) Ted might have been held up...

d) Luggage should not be left...

e) Must we finish...

f) When I woke up, I could hear...

g) I didn't have to wait long...

3. 1c 2c 3a 4b 5a 6c 7d