该部分共有20 小题。在一篇240-280词的文章中留下20个空白，要求考生从每题所给出的四个选项中选出最佳答案。

　　答题时应该考虑以下几个方面：1)通读全文，考虑上下文的含义;2)运用逻辑推理;3)注意惯用法和固定搭配关系。

　　Read the following text .Choose the best word or phrase marked A. B. C .or D for each numbered blank.

　　We often hear the_1_ “Bug” while using computers. But what is a bug? In computer science, a bug _2_ an error in software of hardware. In software, a bug is an error in coding or logic that causes a program to malfunction or to _3_in correct results. Minor bugs, for example a cursor that does not behave as _4_can be inconvenient or frustrating, but not damaging to _5_. More severe bugs can cause a program to “hang” (stop responding to _6_and might _7_the user with no _8_but to restart the program. Losing whatever _9_ work had not been saved. In _10_case, the programmer must find and correct the error by the _11_ known as debugging. Because of the _12_risk to important data, commercial application programs are tested and _13_ as completely as possible before release .Minor bugs found after the program becomes _14_are corrected in next update; more _15_bugs can sometimes be fixed with special software, called patches, that circumvents or otherwise _16_its effects. In hardware, a bug is a recurring _17_problem that prevents a system or set of _18_from working together properly. The_19_ of the term reputedly goes back to the early days of computer at Harvard University was _20_to a moth caught between the contacts of a relay in the machine.

　　1. a. wording b.term c.diction d.insect

　　2. a. recurs to b.prefers to c.attributes to d.refers to

　　3. a. produce b. achieve c. recreate d.attain

　　4. a.expect b.expectation c.expecting d.expected

　　5. a. information b.material c.memory d.news

　　6 a.commands b.monitor c.control d.supervision

　　7. a. grant b.retain c.leave d.reward

　　8. a.alternative b.objective c. collective d.derivative

　　9. a.prestigious b. precarious c.previous d.precious

　　10.a.both b.either c. neither d. none

　　11.a.process b. operation c.performance d.action

　　12.a.promising b.potential c. prospective d.probable

　　13.a.debugged b.analyzed c.released d.removed

　　14.a.accessible b.affable c.available d.adaptable

　　15.a.minor b.major c.important d.severe

　　16.a.alleviates b.worsens c.reduces d.enhances

　　17.a.mental b.physical c.formal d. substantial

　　18.a. ompound b.compositions c.components d.composure

　　19.a.beginning b.start c.source d.origin

　　20.a.tracked b.traced c.followed d.detected