In many high schools，there are strict rules about using mobile phones. If your phone rings in class，for example，the teacher will be very angry.

Every mobile phone has a ringtone (铃声). It tells you that someone is calling you. Now，there is a ringtone called “mosquitotone (蚊子铃声)”. Using it，students can receive calls and text messages (短信) in class but the teacher will not realize what is happening. How?

Mosquitotone has a special sound. Only children and teenagers can hear it. As we get older，we are unable to hear some sounds with high frequencies (频率). As a result，a child or teenager can hear the mosquitotone ringtone, but it’s_inaudible_to someone 20 or older.

But sometimes，people over 20 can hear the ringtone. One British student’s phone uses mosquitotone. In class，the student’s phone rang. The 32­year­old teacher looked at the student and became unhappy. “I heard that. You know the rule：no mobile phone in class.”

Not all the students are interested in mosquitotone. Jerry Jones，a high school student of 17，says，“Using mosquitotone too often is bad for our hearing. I may use it for pleasure，but not in class. It’s unfair to the teachers！”

What do parents think of mosquitotone？“I think it is perfect for places like movie theaters，” says Connie Neeson,44.“Think about it. Yon’re watching a film and someone’s mobile phone rings. Mosquitotone is good because many people don’t hear it. However，it also has a bad influence on their study if students use it in class.”

1.Mosquitotone works because ________.

A. it is very loud                  B. it has no sound

C. it has a beautiful sound         D. it uses high frequencies

2.The under lined part “it’s_inaudible_to” means “________”．

A. it can’t be seen by             B. it can’t be heard by

C. it isn’t popular with           D. it isn’t healthy for

3.The 32­year­old teacher felt unhappy because the student ________.

A. was late for class  B. didn’t do his homework

C. couldn’t answer her question          D. was using a mobile phone in class

4.Connie Neeson thinks that mosquitotone ________.

A. has no bad influence             B. is unfair to the teachers

C. has its advantage and disadvantage  D. can’t be used in any public place

 

In recent years, the Earth has been getting warmer. Average temperatures have risen. Possibly this is natural, but probably we are causing it．Modern people use a lot of electricity and drive a lot of cars. This puts carbon dioxide into the air and helps to make the planet warmer. When we hear this news, we may smile. No one likes long, cold winters, but, unluckily, there are many bad points about a warmer Earth.

First, the ice at the Poles melts and becomes water. The result is that the sea level becomes higher. Low islands will disappear. Cities on the coast will be in danger from the sea. Will Tokyo, Bangkok, Hong Kong and Shanghai become like parts of Holland – lower than the sea? Possibly we will have to build walls to keep the water out. Typhoons will become even more dangerous and frightening.

Sadly, the second point is that storms will become bigger. Super-typhoons will be born in the Pacific and do great damage to East Asia. The same will happen to the Eastern United States.

As the weather changes, some places that now have rain will become dry. The farmers will not be able to grow plants. Maybe some dry places will become wet – we don’t know, but we will soon find out, and the change will cause many problems. There might be wars because of it.

1  What will happen to low islands when the Earth gets warmer and warmer?

     A. They will melt and become water.                B. They will be under the water.

     C. They will become higher.                                   D. They will keep out the water.

2   In the last sentence, “it” refers to ________.

     A. the change of weather                           B. the power of the United States

     C. the ice at the Poles                                   D. the average temperature

3  Which of the following sentences is false?

     A. Shanghai will possibly build walls to prevent the water, like parts of Holland.

     B. The farmers will not be able to grow plants because of the dry weather.

     C. Electricity puts carbon dioxide into the air.

     D. The warmer the Earth is getting, the higher the average temperature is.

4   Which is the best title of this passage?

     A. The Earth Is Getting Warmer                     B. Global Warming Problems

     C. We Made the Earth Warmer                       D. How to Protect the Earth

                                 

 The boy is ________ the room.

A．on               B．in                C．at               D．under