. _____ can be enjoyed until you have a deep understanding of the low-carbon lifestyle.
| A．Something | B．Nothing | C．Few | D．Much |
My dictionary _________, I have looked for it everywhere but still ________ it.
| A．has lost, don’t find |
| B．is missing, don’t find |
| C．has lost, haven’t found |
| D．is missing, haven’t found |
The students ________ busily when Miss Brown went to get a book she ______ in the office.
| A．had written, left | B．were writing, has left |
| C．had written, had left | D．were writing, had left |
By _____, water can be changed into gas.
| A．heating | B．being heated | C．having heated | D．heated |
Mr. Green is said _____ an experiment to prove the new method of solving the problem when young.
| A．to do | B．to have done | C．to be doing | D．to have been doing |
You will see this product made in this factory _____ wherever you go.
| A．to be advertised | B．advertised | C．advertise | D．advertising |