问题 单项选择题

关于Unix操作系统的描述中,正确的是______。

A.Unix由内核和外壳两部分组成

B.内核由文件子系统和目录子系统组成

C.外壳由进程子系统和线程子系统组成

D.内核部分的操作原语对用户程序起作用

答案

参考答案:A

解析:[知识点] UNIX的结构与特性[评析] 在系统结构上,UNIX可以分为两大部分:一部分是操作系统的内核,另一部分是核外程序。内核部分又由两个主要部分组成,它们是文件子系统和进程控制子系统。文件子系统对系统中的文件进行管理,并提供高速缓冲机制。进程控制子系统负责进程的创建、撤销、同步、通信、进程调度以及存储管理。核外程序则由用户程序和系统提供的服务组成。

改错题

短文改错。

      假定英语课上老师要求同桌之间交换修改作文,请你修改你同桌写的以下作文。文中共有10处语言错误,每句中最多有两处。每处错误涉及一个单词的增加、删除或修改。

增加:在缺词处加一个漏字符号(∧),并在其下面写出该加的词。

删除:把多余的词用斜线(/)划掉。

修改:在错的词下划一横线,并在该词下面写出修改后的词。

注意:1.每处错误及其修改均仅限一词;

2. 只允许修改10处,多者(从第11处起)不计分。

Dear friends,

      I'm awfully sorry to hear that horrible and severe earthquake unexpectedly hit your hometown.

Faced with such a rarelyseen disaster, you remain as calm and strongwilled that we are all moved to

tear. A friend in need is a friend indeed. Think about your present situation, you can not wait a minute

to make every bit of our effort to help you. I, as for chairman of the Students' Union, on behalf of all

my schoolmates, express our most sincerely pity and care for you. Besides, we made a donation of

120,000 yuan to you, expecting that it can help you go through the difficult. A better hometown can

be rebuilt. Remember we won't  be far away as you need any help!

                                                                                                      Y ours sincerely,

                                                                                                            Li Hua

单项选择题 B1型题