—Have you seen Jack recently?
—No. He for another company now.
| A．is working | B．had worked | C．worked | D．was working |
___in the air, this kind of steel become harder and harder.
| A．Cooling | B．Having cooled | C．Being cooled | D．Cooled |
In a chemical change, energy cannot be created ,____.
| A．nor can it be destroyed | B．not it be destroyed | C．so can’t it not be destroyed | D．either it cannot be destoryed |
The Loisels did what they could ___ the debts.
| A．to pay off | B．to pay for | C．paid off | D．paid for |
The teacher entered the classroom, _____.
| A．with book in hand | B．book in hand | C．with book in his hand | D．book in his hand |
Let’s have another look, ___?
| A．will you | B．shall we | C．do you | D．don’t you |