Ответ:

1. They aren't big enough for her, they are too tight.
2. My new haircut looks too old-fashioned, it isn't modern enough.
3. He has forgotten his homework too often. He isn't careful enough.
4. Daisy can't get over the fence because it isn't low enough.
5. Nick didn't want the race because he was too slow.
6. A chihuahua can't catch a German shepherd because it isn't fast enough.
7. His car is too old to be safe and he isn't careful enough about that.
8. Brenda doesn't learn enough, she is too lazy.
9. Jenny can't play football because she can't kick hard enough.
10. Joe can't lift the piano because he isn't strong enough.
11. You can't put your feet on the sofa with your shoes on. They are too dirty.

Объяснение:

Too - имеет не сильно много, но разных от ситуации значений. Это как и "тоже", так и "слишком".

Enough - достаточно.