B
April 22 is Earth Day. Everyone on earth should care about and protect the earth! The earth has warmed by about 1°F(华氏度) over the past 100 years, but why and how? Well, scientists are not quite sure. Maybe the earth gets warmer and warmer on its own. But many scientists say that people are doing many things which make the earth warmer.
First, the greenhouse effect (温室效应) is a very important reason for the change of the earth. People give out too much energy into the air every year. It makes the earth warmer. Climate (气候) change is another important reason. Sometimes it becomes too hot and sometimes too cold. Sometimes there is too much rain and sometimes too little. The change of the climate makes the earth warmer. In turn, the warmth of the earth changes the climate, too.
People can affect the earth's air, land and water. As for us, we can do many things to protect the earth. For example, we can use fridges less. We can tell more people about protecting the earth.
6．Earth Day is probably created for people to________．
A. learn more about the earth B. make full use of the earth
C. take better care of the earth D .study the warmth of the earth
7．We can infer (推断) from the passage that the reasons for the warmer earth are____ now.
A．not very clear B. completely secret C. well known D. not given
8．The greenhouse effect comes from ________．
A．sea rising B. climate change
C. nature's unbalance D. people's activity
9．According to the passage, ________ may affect each other.
A．animals and islands B．climate and the warmth of the earth
C．fridges and animals D．sea level and the growth of plants
10．The passage mainly tells us that ________．
A．there is more rain now B. we should protect the earth
C．we must stop pollution D. sea level is getting higher.
