Ответ:
Task 1
1. sports centre
2. gallery
3. snack
4. stadium
Task 2
1. mustn't
2. needn't
3. needn't
4. mustn't
Task 3
Ann has to type letters and answer the phone, but she doesn't have to losk the office. And I have to study harder and do my homework regularly, but I don't have to come to school at 7.30.
Task 4
Late-later-the latest
rich-richer-the richest
hungry-hungrier-the hungriest
good-better-the best
little-less-the least
many-more-the most
dangerous-more dangerous-the most dangerous