Through the open window we saw on the floor the happy father lying （） his stomach, his daughter riding excitedly on his back.

Usually the teachers will be busy （） the test papers af...

单项选择题Usually the teachers will be busy （） the test papers after an examination.

The problem, according to the experts, is （） we should ...

单项选择题The problem, according to the experts, is （） we should do with the salty land.

As we all know, the government is now making every （） t...

单项选择题As we all know, the government is now making every （） to set up a harmonious society.