用所给词的适当形式填空

1. There are so many people in the street! It is really too ____ (crowd), isn't it?

2. At school we are all ____ (friend) to each other.

3. I've been ____ (wait) for you for one hour.

4. There is a lot of sand on the beach, so it’s _____ (sand).

5. Can you see the _____ (baby) over there? They are twins.