问题 单项选择题 共用题干题

计算机执行程序所需的时间P可用P=I×CPI×T来估计,其中I是程序经编译后的机器指令数,CPI是执行每条指令所需的平均机器周期数,T为每个机器周期的时间。RISC计算机采用(1)来提高机器的速度。它的指令系统具有(2)的特点。指令控制部件的构建,(3)。RISC机器又通过采用(4)来加快处理器的数据处理速度。RISC的指令集使编译优化工作(5)。

空白(5)处应选择()

A.更简单

B.更复杂

C.不需要

D.不可能

答案

参考答案:A

选择题
阅读理解

阅读理解。

     The Internet has become part of teenage life. There's a report on 3 375 students in seven Chinese cities.

It says that 38% of them believe they use the Internet often. While most of them get useful information and

use the Internet to help in their studies, some are not using it in a good way. Many are playing online games

too much. A few even visit websites they should not look at. Bad things can happen if young people spend

too much time on the Internet.

     In order to help young people use the Internet in a good way, a textbook has been used in some Shanghai

middle schools this term. It uses real examples to teach students all about good ways of using the Internet.

It gives useful advice such as it's good to read news or find helpful information to study. Some students also

make online friends.

     Teachers and parents all think the book is a very good idea. It will teach students how to be a good person

in the online world. It will be a guide for teens using the Internet and keep students away from bad sites.

1. The report shows that _____ of the 3 375 students are playing online games too much.

A. 38%

B. most

C. many

D. a few

2. How does the textbook teach students?

A. With real examples.

B. With pictures.

C. With music.

D. With tapes.

3. Which of the following useful advice is NOT mentioned in the passage?

A. Read news.

B. Find information.

C. Make friends.

D. Watch films. 

4. What do teachers and parents think of the textbook?

A. It's a very good idea.

B. It's a foolish idea.

C. It keeps students looking at bad sites.

D. It can't teach students how to be good.