Ответ:

1.

If you get there early, you'll get the best seats

If I need your help, I'll phone you

If the bus doesn't come, we'll take you in our car

If it rains tomorrow, we won't go to the park

When Jo and Mike arrive, I'll offer them a, drink

When the train stops, the doors will open

When we go into town, we'll have lunch there

When the course finishes, I'll go back to Japan

2.

1 b

2a

3 b

4 b