发电机冷却介质的置换为什么要用CO2作中间气体？

常见的电动挡板故障有哪些？

In the 1500s, South American fishermen said that the sea became warmer every few years. They gave this special event a Spanish name ’El Nino’, meaning ’the baby’. It is called ’the baby’ because it arrives around Christmas.

El Nino is a huge area of warm water in the middle of cold water in the Pacific Ocean. It happens every two to seven years. It moves around the ocean and becomes bigger and smaller at different times. This warm water affects the weather. It is always raining over El Nino. El Nino contains a lot of energy. Scientists think this energy is formed when wind comes from the northern half of the world. The winds blow across warm sea water in the south. When the strong wind hits the warm water, violent weather happens. Scientists think that El Nino existed for many thousands of years.

El Nino affects every person in the world because it affects the entire world’s weather. It can bring the rain that farmers need. It can bring storms that destroy homes. It can mean that fishermen cannot catch fish, and it can bring floods. There is nothing we can do about El Nino. It is an event of nature. We can help the world’s weather by trying to stop the greenhouse effect and air pollution. The most important job for scientists is to learn how to predict when El Nino is going to bring dangerous weather. Then, people can try to prepare for storms, floods and droughts. New technology like satellite pictures and temperature measuring equipment can help. Still, it is very hard to say when or where El Nino will cause damage.

小题1:El Nino is ______.

A．a storm that hits every two years

B．a huge area of warm water

C．a wind from the south

D．some cold water in the Pacific Ocean小题2: It happens ______.

A．every year

B．every month

C．every seven years

D．every two to seven years小题3:El Nino ______.

A．makes the weather better

B．affects the weather

C．gives the weather energy

D．predicts the weather小题4:It is always______ over EI Nino.

A．sunny

B．cloudy

C．rainy

D．windy小题5:El Nino affects ______.

A．everybody

B．just farmers

C．only fishermen

D．only students小题6: We can help the world’s weather by______.

A．finding out more about El Nino

B．being careful during the floods

C．driving cars

D．stopping the greenhouse effect小题7:______helps to predict El Nino.

A．Looking out of the window

B．Checking the weather each day

C．Satellite pictures

D．New boats

下列各项，不属于肾精不足证的是（）。

A.小儿生长发育迟缓

B.发脱齿松，健忘恍惚

C.男子精少不育，女子经闭不孕

D.舌淡，脉弱

E.腰酸软而痛

超滤法是用于（）分离的膜滤过方法。

反应类平整度仪有（）。

A.时间稳定性差

B.转换性差

C.不能给出路表真实断面

D.以上所说的都不对