问题 单项选择题

IP服务不具有以下哪个特点

A.不可靠

B.面向无连接

C.Qos保证

D.尽最大努力

答案

参考答案:C

解析: IP服务的三个主要特点为:不可靠的数据投递服务;面向无连接的传输服务;尽最大努力投递服务,Qos保证不是IP所提供的服务。

阅读理解

阅读理解。

     Teachers at American colleges and universities have many different teaching methods. Some teachers

give homework and check homework every day, and students in their classes have to take many exams.

Some teachers give only writing tasks. Some teachers always follow a course outline and usually use the

textbook. Others send students to the library for tasks.

     The atmosphere in some classrooms is very formal. Students call their teachers Professor (教授) Smith,

Mrs. Jones and so on. Some teachers wear business clothes and give talks. Other classrooms have an informal ( 非正式的 ) atmosphere. Students and teachers discuss their ideas. Teachers dress informally, and students

call them by their first names. American teachers are different in their teaching styles.

     At most American colleges and universities, libraries and learning centers can be used by students at any

time. They can often use tape recorders, video machines and computers. They can buy books, notebooks and

other things at campus stores. There are also services (服务) to students. They can get advice on their

problems from their teachers. Colleges and universities usually offer facilities (设施) to students. Some schools

have swimming pools and tennis courts. Most have fast food restaurants.

1. At American colleges and universities, some teachers _________.

A. never give their students any homework

B. give classes in the library

C. give only writing tasks

D. only give their students writing exams

2. In an informal class, _________.

A. students call their teachers Professor Smith, Mrs. Jones and so on

B. students discuss their ideas with their teachers

C. students have to take many exams

D. teachers dress formally

3. The underlined word "campus" means _________ in Chinese.

A. 校园

B. 工厂

C. 社区

D. 广场

4. According to the passage, most schools in America have _________.

A. swimming pools

B. fast food restaurants

C. tennis courts

D. basketball courts

5. Which of the following is not mentioned in this passage?

A. Teaching methods.

B. Teaching styles.

C. College facilities.

D. University dinning rooms.

单项选择题