It is ________ the customers' needs that has made chain stores so popular in big cities in China.
You are_____ to hand your paper in before the class is over.
The father as well as his three children____ skating on the frozen river every Sunday afternoon in winter
The little girl ______go to the cinema rather than ______ at home alone that night.
The alarm ________ when the thieves got in.
The two boys ______when climbing the mountains.