We will have finished ________ Unit 15 by April. We can review all the lessons.
| A．learning | B．learn | C．learned | D．to learn |
A hard-working man ______ become a great scientist, but a great scientist _______ be a hard-working man.
| A．can’t; can | B．may not; must |
| C．can’t; must | D．may not; can |
We work together to achieve our common purpose: _________ world that is safer, cleaner and healthier than __________ one we are living in.
| A．the , / | B．a , / |
| C．the , the | D．a , the |
根据句意和汉语注释，写出单词的正确形式。China is ______ (富有)and more powerful than ever before.
Everyone is _____________(料想) to know the rules.
Ren Rong has devoted himself to cultural _________(对话) between China and West
The researchers hope their new ______(发现) can be used to make objects that are difficult or impossible to replace.
—May I ask a question after class, Sir?
—____, but not during my lunch break.
| A．I'm sorry | B．Any time | C．Certainly | D．Go ahead |
The students stop __________ when the teacher came in.
| A．to talk | B．talking | C．talked | D．talk |