The reason ___ he can’t come is ______ he has to work late.
| A．because; that | B．that; that | C．why; that | D．why; because |
His father feels ___ his duty to help others.
| A．this | B．it | C．that | D．what |
I don’t think this question is worthy ___.
| A．to consider | B．to be considered | C．considering | D．of considering |
There were three ___ eggs in the basket.
| A．dozen | B．dozens | C．dozens of | D．dozened of |
The earth is 49 times ___ the moon.
| A．as bigger as | B．so big as | C．the size of | D．of the size of |
The machine has begun to ___.
| A．have its work | B．take its work | C．do its work | D．show its work |