________China has successfully launched its Shenzhou Ⅵ with two astronauts in it has shocked the world

Don’t keep the boy __________ in the rain. He will fall ill.

He came to a point ______ there was no more road to follow, and before him he could see nothing but a thick forest.

_____ does your mother usually go to the office—By bus.

He had to pause from time to time to wipe the sweat from his forehead, because the air-conditioning system ______________.