There are __________ (很多原因) why we shouldn't do it.
It __________ (她突然想到) that she could turn to John for help.
The photos will show you __________ (我们村子是个什么样子).
We haven't settled the problems of __________ (她有没有必要去国外学习).
Don't put off till tomorrow __________ (今天能做的事情).