用括号内所给词的适当形式填空。
1. — The (develop) of new products is important to our company. Do you know?
— Yeah, it is our duty to try our best to deal with it.
2. I think the most helpful (invent) is the light bulb (电灯泡). It gives people more time to work and
play.
3. The foreigner spoke English so (quick) that I could hardly understand what he said.
4. The large population of China has caused many (difficult). For example, many farmers have no
farmland to grow crops on.
5. — What do you think of the English (train) school?
— It is great. I have improved my English a lot.
