. –You see, I’m poor in maths, you are not good at English, and……--That’s_________we should help each other.
It was only then ______ I began to have doubts about whether my story had ever been told.
The secretary worked late into the night, ______ a long speech for the president.
There is no doubt _______ nearsightedness is a serious problem among the youth of our country.
You needn’t have ________ the speaker when he was speaking; there was enough time afterwards for you to ask questions.
It’s helpful to put students in a situation _______ they can learn how to cooperate with each other.