Many students preparing for the midterm examination.
| A．are engaging in | B．are engaging themselves |
| C．are engaging themselves | D．are engaged in |
It is thought that one billion people I the world, _____is half the word’s workers, earn their living by farming.
| A．if | B．that | C．which | D．what |
I think whoever makes____contributions to the company than the others should get____income.
| A．greater; a highest | B．more greater; a higher |
| C．greater; the highest | D．more greater; the higher |
Our teacher is always busy preparing lessons until 11 o’clock at night, _____we students have gone to sleep.
| A．that time | B．by which time | C．by that time | D．which time |
The news _____is spreading around the airport is _____a heavy storm is coming.
| A．what; / | B．that; that | C．/; that | D．that; which |
He is taller than he ______.
| A．used | B．used to be | C．used to | D．used to do |