Liping works very hard at his lessons .He didn’t get the first place in the exam ,_______.
That was the last time I saw my father before he _____.
The experiment __ to be .
Many _______ of years later, the first extremely small plants began to appear on the surface of the water.
As a child, Franc _____.
They won’t buy any new clothes because they ________ money to buy a new car.