This new kind of chemicals will help keep the air, soil and water________ from pollution．
| A．free | B．empty | C．loose | D．short |
一"Peter, have you got your new flat furnished?
—Yes. I ______ some used furniture and it was a real bargain.
| A．will buy | B．have bought | C．bought | D．had bought |
These diagrams are especially helpful when we have a concrete problem ______ at hand.
| A．be solved | B．to solve | C．solved | D．being solved |
This kind of gel pen which ______ smoothly is quite popular with students.
| A．is written | B．is writing | C．wrote | D．writes |
It is the bus driver who should ______ the safety of the passengers.
| A．answer for | B．search for | C．stand for | D．go for |
I’m very grateful to my high school teachers, without ______ help I wouldn’t be so excellent.
| A．whom | B．their | C．which | D．whose |