It will be at least three years _______ we get to meet again.

In the continuous high temperature weather, it is not to fit to gather. That is      we cancel the discussion

______ you are familiar with the author’s ideas, try reading all the sections as quickly as possible. 

Playing balls together is a kind of activity_____ every player needs to be well-cooperated together.

We shouldn’t think the question of ________ they are poor or rich is important.