Passage 3

　　Today we do not measure the speed of computer functions in minutes,or in seconds,or even in hundredths(1/100)or thousandths(1/1000)of seconds.We measure the speed of computers in billionthsof seconds.We call one billionth of a second a nansecond.

　　Computers were not always so fast,of course.In fact,at one time,the human mind could perform calculations faster than a computer.Let us look briefly at the development of the computer.We will see that the Computer Revolution happened only when computers developed their incredible speed.

　　In 1833,Charles Babbage built his “analytical engine”，the first computing machine.His colleague,Augusta Ada,the Countess of Lovelace,continued Babbage's work.She became the first programmer in history.Fifty years later,Herman Hollerith designed a machine that counted automatically.This machine was used to count the number of people in the United States for the 1890 census.It used a system of punch cards.Hollerith's company,by the way,eventually became IBM(International Business Machines)。

　　The first large digital computer was built by IBM in 1944.It was called the Mark I.Then in 1947,IBM built the Mark II.Today we cannot imagine how slow these computers were,just as we cannot imagine how fast modern computers were,just as we cannot imagine how fast modern computers are.These computers needed one or two seconds to perform one calculation.In these same years,electronic computers developed.They were much faster than the huge,slow Mark I and Mark II.ENIAC is the name of the first all-electronic computer,built in 1944 and 1945.The world was amazed to learn the speed of this computer:5,000 additions per second,and 300 multiplications per second.Today we smile at these “slow”speeds.

　　Then in 1960 the real“revolution”began with the introduction of integrated circuits.Today,thousands of transistor circuits can fit on one small silicon chip.As a result,we now measure the speed of computers in nanoseconds.

　　8.()According to the passage,which of the following is the most important feature of a modern computer?

　　A.Its small size.

　　B.Its analytical power.

　　C.Its incredible speed.

　　D.Its system of punch cards.

　　9.()What brought about the speed of computers in nanoseconds?

　　A.The invention of digital computer.

　　B.The introduction of integrated circuits.

　　C.The design of an automatic counting machine.

　　D.The founding of Hollerith's IBM.

　　10.()The best title for this passage would be ______.

　　A.The Computer and the silicon chip

　　B.The Computer Revolution:Birth of the Nanosecond

　　C.Five Thousand Additions in One Second

　　D.IBM:International Business Machines Corporation

　　三、完形填空，并将所选答案之字母填在题前的括号内。(10%)

　　When you make up your mind to buy a house,most of the things you are concerned with are practical,(1)deciding whether you can afford it or the house is too (2)the station.You do not usually get the chance to (3)out about the neighbors before moving house.Flats are on the whole worse (4)houses from this point of view,but we have been lucky.When the old lady in the flat (5)we had a little boy,she was worried.‘I hope he won't make too much noise’，she said .Fortunately,the man underneath us has a full-time (6)in the city,so he doesn't hear Tom running up and down all day.His main interest is (7)the communal garden.He told us when we moved in that we were (8)for mowing the lawn once a month.The young couple who live on the same (9)as us are very friendly;their only fault is that they are very forgetful.The day we arrived,Joyce came to ask us if she could (10)a phone call to Dave at work.She had come out without her keys and couldn't get back into her flat.

　　1.()

　　A.as

　　B.such

　　C.like

　　D.example

　　2.()

　　A.far to

　　B.far away

　　C.far from

　　D.the far distance

　　3.()

　　A.find

　　B.look

　　C.see

　　D.discover

　　4.()

　　A.over

　　B.than

　　C.if

　　D.compare to

　　5.()

　　A.saw

　　B.looked

　　C.gave

　　D.expected

　　6.()

　　A.job

　　B.wage

　　C.business

　　D.employment

　　7.()

　　A.putting up

　　B.sorting out

　　C.looking after

　　D.getting down to

　　8.()

　　A.interested

　　B.careful

　　C.thankful

　　D.esponsible

　　9.()

　　A.building

　　B.level

　　C.ground

　　D.floor

　　10.()

　　A.do

　　B.pay

　　C.make

　　D.reach