In recent years,_ __global warming is becoming__ _concern for people all over the world．
| A．the; the | B．不填；不填 | C．不填；a | D．the; 不填 |
The teacher knows that you are always the first ________ to the classroom since last september.
| A．coming | B．to come | C．came | D．has come |
We can’t take part in the competition ________ we get our student card.
| A．before | B．if | C．While | D．as |
It was announced that only when the examination papers were handed in ________to go out of the classroom．
| A．the students would be permitted | B．had the students been permitted |
| C．would the students be permitted | D．the students had been permitted |
As a result of the heavy snow，two-thirds of the buildings in the area.
A. need to repair B.needs to repair C.needs repairing D need repairing.
—It’s only ten minutes’ walk; I could have got there on foot.
— Yes. A taxi _______ not at all necessary.
| A．was | B．had been | C．has been | D．is |