The professor managed to find some grounds (facts)_________his arguments．
| A．to be based on | B．to base on |
| C．which to base on | D．on which are based |
It was because he was seriously ill _________ he was late for school.
| A．that | B．which | C．so | D．what |
I failed in the examination last week and I regret _____________ hard.
| A．not to study | B．not studying | C．have not studied | D．did not study |
When Tony came to, he found himself ___________ in hospital with his teachers and classmates around him.
| A．lying | B．laying | C．laid | D．lied |
We __________3,000 English words by the end of last year.
| A．have learned | B．had learned | C．learned | D．learn |
We donated some money and clothing to the children ________ parents were killed in the earthquake.
| A．their | B．which | C．whose | D．who |