西交《专业英语》在线作业-00001


------------------------
1.A transformer is a device that can convert one ac voltage to another ac voltage through the action of _____.
A.an electric circuit
B.a magnetic field
C.an electric field
D.a coupling circuit
答案请点我要此答案，或联系QQ

2.The hydropower is well suited for switching according to _____ command to meet changing power needs.
A.a consumer’s
B.a user’s
C.a dispatcher’s
D.an operator’s
答案请点我要此答案，或联系QQ

3.These are all (_______) demands.
A.reasonable
B.available
C.logical
D.formal
答案请点我要此答案，或联系QQ

4.Lenin stressed that it is precisely the people who (_______) history.
A.invent
B.imagine
C.create
D.discover
答案请点我要此答案，或联系QQ

5.________ a concert next Saturday?
A.There will be
B.Will there be
C.There can be
D.There are
答案请点我要此答案，或联系QQ

6.—Are you sure that you’ve met him before? — ___I’m mistaken.
A.Unless
B.If
C.When
D.Though
答案请点我要此答案，或联系QQ

7.When John came in, she (_______) her talk with Linda and talked to him.
A.broke off
B.called off
C.carrird off
D.passes out
答案请点我要此答案，或联系QQ

8.An expansion slot is a long, narrow socket on the motherboard into which you can plug _____.
A.an expansion card
B.a modem
C.a network card
D.a sound card
答案请点我要此答案，或联系QQ

9.A computer’s microprocessor only understands _____ in binary form.
A.high-level languages
B.machine language
C.human languages
D.assembly language
答案请点我要此答案，或联系QQ

10.They thought the program was (_______) investigating．
A.worth
B.worthy
C.worthwhile
D.worthing
答案请点我要此答案，或联系QQ

11.These heavy walls expressed man's fear of the outer world and his need to find (_______) .
A.prevention
B.protection
C.preservation
D.preparation
答案请点我要此答案，或联系QQ

12.Be sure to (_______) your work at the end of the exam.
A.look over
B.hang up
C.set aside
D.catch sight of
答案请点我要此答案，或联系QQ

13.If they come, we ________ a meeting.
A.have
B.will have
C.had
D.would have
答案请点我要此答案，或联系QQ

14.The notebook computers use _____ as standard display equipment.
A.CRT display
B.LCDs
C.LED
D.TV screen
答案请点我要此答案，或联系QQ

15.The generator voltages are usually stepped up to the transmission voltage level by _____.
A.series capacitor
B.parallel reactors
C.step-up transformers
D.step-down transformers
答案请点我要此答案，或联系QQ

16.We go to the cinema (_______) a week.
A.often
B.once
C.seldom
D.usually
答案请点我要此答案，或联系QQ

17.The system’s characteristic equation can be used to determine _____ of a linear time-invariant system.
A.the stability
B.magnitude of the steady-state error
C.the controllability
D.the observability
答案请点我要此答案，或联系QQ

18.Oh, sorry to bother you. ----- (_______) .
A.That's OK
B.No, you can't
C.That's good
D.Oh, I don't know
正确答案:false

19.The objective of the optimal economic operation of power systems is _____.
A.to minimize the total production cost
B.to maintain frequency constant
C.to maintain voltages constant
D.to ensure balance between generation and load
答案请点我要此答案，或联系QQ

20.(_______) finishing his homework, he had to stay home at the weekend.
A.Not having
B.Having not
C.Being not
D.Having not being
答案请点我要此答案，或联系QQ

21.——Excuse me, but there’s no smoking on this flight .——Oh , I ___that . Sorry, I won’t do it again.
A.don’t know
B.didn’t know
C.won’t know
D.haven’t known
答案请点我要此答案，或联系QQ

22.—Don’t you think hard work is what makes people succeed?— ___.
A.I couldn’t agree more
B.I hope so
C.I’ve got it
D.Wish you success
答案请点我要此答案，或联系QQ

23.Some schools teach but fail to (_______) their students.
A.educate
B.instruct
C.enlighten
D.editorial
答案请点我要此答案，或联系QQ

24.——I’m sorry I stepped outside for a break . I was very tired.——There’s no ___for this while you are on duty .
A.excuse
B.reason
C.cause
D.explanation
答案请点我要此答案，或联系QQ

25.___, and we’ll know the results of the contest.
A.Another 3 days
B.Three days later
C.After 3 days
D.In three days
答案请点我要此答案，或联系QQ

26.The proposal seems quite good, but I can’t easily (_______) without all the facts.
A.join
B.judge
C.say
D.speak
答案请点我要此答案，或联系QQ

27.Although he had looked through all the reference material on the subject, he still found it hard to understand this point and her explanation only (_______)to his confusion.
A.extended
B.amounted
C.added
D.turned
答案请点我要此答案，或联系QQ

28.He was then the only ___among the___there.
A.person asleep, people present
B.asleep person, present people
C.person asleep, present people
D.asleep person, people present
答案请点我要此答案，或联系QQ

29.The teacher advised Joe to___before deciding to quit school.
A.think about
B.think twice
C.think up
D.think over
答案请点我要此答案，或联系QQ

30.So far is known, the original manuscripts of Shakespeare’s plays are no longer (_______) .
A.in wonder
B.in general
C.all in all
D.in existence
答案请点我要此答案，或联系QQ

31.Within industries, companies are always trying to develop products that are one step better than___ of other companies.
A.ones
B.that
C.those
D.all
正确答案:false

32.The DC-DC converts _____ input to _____ output.
A.direct current, alternating current
B.direct current, direct current
C.alternating current, alternating current
D.alternating current, alternating current
正确答案:false

33.The electric machine that operates at speeds above synchronous speed works in _____ region.
A.motoring
B.generating
C.plugging
D.stopping
答案请点我要此答案，或联系QQ

34.The wide application of operational amplifiers lies in advantage of using _____.
A.positive feedback networks
B.large open-circuit gain
C.negative feedback networks
D.small output impedance
答案请点我要此答案，或联系QQ

35.In the root-locus method the actual time response of a system can be obtained by means of _____.
A.the inverse Fourier transform
B.the inverse Laplace transform
C.the Fourier transform
D.the Laplace transform
答案请点我要此答案，或联系QQ

36.I believe we’ve met somewhere before. --- No, (_______) .
A.it isn’t the same
B.it can’t be right
C.I don’t think so
D.I’d rather not
答案请点我要此答案，或联系QQ

37.The advertisement said that an expanding company wished to (_______) a secretary at their head office.
A.explore
B.exploit
C.employ
D.accept
答案请点我要此答案，或联系QQ

38.The aim of our training is to teach the students to have the ability of tackling problems (_______) .
A.of their own
B.on their own
C.to their own
D.for their own
答案请点我要此答案，或联系QQ

39.My passport (_______) last month, so I will have to get a new one.
A.elapsed
B.expired
C.ended
D.terminated
答案请点我要此答案，或联系QQ

40.After stopping for a few minutes, the bus moved (_______) to its next stop.
A.forward
B.off
C.with
D.on
答案请点我要此答案，或联系QQ

41.We have come to a critical moment. You must take immediate (_______) .
A.act
B.action
C.activity
D.doings
答案请点我要此答案，或联系QQ

42.Her eyes were filled (_______) tears.
A.of
B.with
C.in
D.along
答案请点我要此答案，或联系QQ

43.“Have you seen Lao Wu recently?” “It looks (_______) he would return home tomorrow.”
A.like
B.as
C.as if
D.that
答案请点我要此答案，或联系QQ

44.Could I use your dictionary for a moment? -----(_______).
A.It's well
B.It doesn't mattter
C.By all means
D.I have no idea
答案请点我要此答案，或联系QQ

45.1
A.A
B.B
C.C
D.D
答案请点我要此答案，或联系QQ

46.All the characteristics that distinguish birds (_______) other animals can be traced to prehistoric times.
A.to
B.between
C.for
D.from
答案请点我要此答案，或联系QQ

47.I would die (_______) marry him!" she screamed.
A.instead of
B.rather than
C.other than
D.more than
答案请点我要此答案，或联系QQ

48.— My best friend’s in a bad mood.— How about ____ her some flowers?
A.giving
B.given
C.to give
D.give
答案请点我要此答案，或联系QQ

49.I think English is as ____ as math.
A.important
B.importanter
C.more important
D.most important
答案请点我要此答案，或联系QQ

50.