李勃良

People in cities use a lot of water—for cooking， washing， drinking， and so on. Rain is the main source （來源） of new water. Unfortunately， it doesn't always rain enough （足够的）. That can be big trouble for cities.

Sometimes， we can help make rain. To do this， a special airplane flies up to the clouds. Then， it lets out some chemicals. These chemicals cause clouds to make rain. This is called “seeding clouds”. Seeding clouds can help bring water to thirsty cities.

【词汇拓展】

1. unfortunately 不幸地 2. fly 飞 3. chemical 化学制品 4. cause 引起;导致 5. thirsty 口渴的

I. 词汇练习

1. Typhoons （台风） ________ a lot of trouble for people and cities.

2. Give the ________ baby something to drink.

3. ________， I can't go with you to the mall.

4. Many birds ________ south in winter.

II. 阅读练习

根据短文内容回答下列问题。

1. Where does new water come from？

A. Rivers      B. Lakes     C. Rain     D. Mountains

2. According to the article， without enough rain ________.

A. people do a lot of cooking B. people use more water

C. cities look for other sources of water D. cities have problems

3. What is “seeding clouds”？

A. A kind of cloud. B. A way to make rain.

C. Chemicals. D. A special airplane.

4. What happens first？

A. Special airplanes let out chemicals.

B. An airplane flies up high in the sky.

C. Cloud seeding causes clouds to make rain.

D. It rains a lot.