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.

辩证联系的含义是（）。

A、概念之间的相互判断、推理等逻辑关系

B、事物或现象之间的相互作用、相互影响和相互制约

C、事物发展过程中直接的本质的关系

D、事物或现象之间界限的不确定性