Seeing the big crowd coming towards him, he started to run down the hill，but____   and went down on his hands and knees in the melting snow.

Corruption is _______ problem in countries across the world, with developing countries often believed to be more serious, although there is no evidence to suggest this is _______case. 

What great trouble the boy _____his father to give up smoking!

I have had my bike _____, and I'm going to have somebody______ my radio tomorrow.

It was dark and he had already lost his ________of direction.