—Jack can't concentrate on his lessons recently.—Yes, that might ____ why he did so badly in the last test.
____you have done might do harm____other people.
The two ladies are ________ the same age, but there seems to be ten years ________ them.
Zhejiang Province lies ______ the east of China and there are some islands ______ its coast.
They did it all____ friendship.
____ has recently been done to provide more buses for the people, a shortage of public vehicles remains a serious problem.