People are _________the use of alternative energy sources. Because the fossil fuels _________will be used sooner or later.

Alice fell into a very deep hole on a sunny afternoon, her fantasy visit to the fairyland ______．

Rather than ______ on a crowded bus, he always prefers _____ a bicycle.

It took the scientists seven days to________Takla Makan________“the sea of death”.

— Anything to drink? What about coffee?— Er… I think I’ll have a cold drink          coffee.