In many high schools there are strict rules about using mobile phones. If your phone rings

问题补充：

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.”

【小题1】Mosquitotone works because .A．it is very loudB．it has no soundC．it has a beautiful soundD．it uses high frequencies【小题2】The under lined part “it’s_inaudible_to” means “”．A．it can’t be seen byB．it can’t be heard byC．it isn’t popular withD．it isn’t healthy for【小题3】The 32­year­old teacher felt unhappy because the student .A．was late for classB．didn’t do his homeworkC．couldn’t answer her questionD．was using a mobile phone in class【小题4】Connie Neeson thinks that mosquitotone .A．has no bad influenceB．is unfair to the teachersC．has its advantage and disadvantageD．can’t be used in any public placeD

答案：

(答案→)D

解析：

【小题1】本文第二段倒数第二句为As we get older，we are unable to hear some sounds with high frequencies (频率).，所表示的含义为随着岁数的变大，我们不能够听到高频率的声音，故本题选D。

【小题2】本文第二段最后一句为As a result，a child or teenager can hear the mosquitotone ringtone, but it’s_inaudible_to someone 20 or older.所表示的含义为儿童能听到蚊子铃声，但是20岁以上就难以听见，故本题选B。

【小题3】本文第三段第二行有两句为the student’s phone rang. The 32­year­old teacher looked at the student and became unhappy. 所表示的含义为学生在课堂上使用手机，老师感到不开心，故本题选D。

【小题4】本文最后一句话的含义为蚊子铃声有它的好处和不好处，故本题选C。