这个盒子可以当作一个玩具箱。

This box can ___serve as a toy box.

这是一部非常有趣的电影，但它也服务于教育目的。

It's a very entertaining movie, but it also ___serves an educational purpose.

那些讨论只是加深了她的恐惧。

Those discussions only ___served to reinforce her fears.