The degree of downward slope of a beach depends on its composition of deposits as well as on the action of waves across its surface（）

单项选择题After our computer network （）for the third time that day, we all went home.

A. crashed
B. collided
C. smashed
D. fell

单项选择题The playwright was known not for his original ideas but for his ______ of ideas that had been propounded by others.