相关试题
【单选题】
— Thanks for your help.___
A. My pleasure.
B. Never mind.
C. Quite right.
D. Don't thank me.
【单选题】
— Hello, my name is Charles Green, but ___ .
A. call my Charles
B. call me at
C. harles C. call me Charles
D. call Charles me
【单选题】
— ___, and how are you?
A. Don't mention it
B. Hm, not too bad
C. Thanks
D. Pretty fast
【单选题】
— I'm sorry. I am late due to the heavy traffic___
A. Well, it's OK.
B. No, it's all right.
C. You are welcome.
D. You are wrong.
【单选题】
— It's rather cold in here. Do you mind if I close the window?___
A. Yes, please.
B. No, please.
C. Sure, please.
D. I don't like it.
【单选题】
___He teaches physics in a school.
A. What does your father do?
B. Who is your father?
C. What is your father doing?
D. Where is your father now?
【单选题】
— Excuse me, how much is the jacket?___ It's 499 Yuan.
A. Oh, no. That's OK!
B. How do you like it?
C. Which do you prefer?
D. Would you like to try it on?
【单选题】
— Could you help me with my physics, please？___
A. No, no way.
B. No, I couldn't
C. No, I can't.
D. Sorry I can't. I have to go to a meeting right now.
【单选题】
— Could I speak to Don Watkins, please?___
A. Speaking, please.
B. Oh, how are you?
C. I'm listening.
D. I'm Don.
【单选题】
— Could I borrow your car for a few days?___
A. Yes, you may borrow.
B. Yes, go on.
C. Sure, here is the key. Enjoy your journey.
D. It doesn't matter.
【单选题】
— Thank you for inviting me.___
A. I really had a happy time.
B. Oh, it's too late.
C. Thank you for coming.
D. Oh, so slowly?
【单选题】
— May I see your tickets, please?___
A. Sure.
B. No, you can't.
C. No, they are mine.
D. Yes, you can.
【单选题】
— Please help yourself to the seafood.___
A. No, I can't.
B. Sorry, I can’t help.
C. Well, seafood don’t suit.
D. Well, I'm afraid I don't like seafood.
【单选题】
— Would you like to go to the concert with us this evening?___
A. No, I already have plans.
B. I'd love to, but I'm busy tonight
C. No, I really don't like being with you.
D. I'm ill, so I shouldn't go out.
【单选题】
— Congratulations! You won the first prize in today's speech contest.___
A. Yes, I beat the others.
B. No, no, I didn’t do it well.
C. Thank you.
D. It's a pleasure.
【单选题】
— Must I take a taxi? No, you___. You can take my car.
A. had better to
B. don't
C. must not
D. don't have to
【单选题】
— We are going to have a singing party tonight. Would you like to join us?___
A. I'm afraid not, because I have to go to an important meeting.
B. Of course not. I have no idea
C. No, I can’t.
D. That's all set
【单选题】
— How was your trip to London, Jane?___
A. Oh, wonderful indeed.
B. I went there alone.
C. The guide showed me the way.
D. By plane and by bus.
【单选题】
— Hey, Tom, what's up?___
A. Yes, definitely!
B. Oh, not much.
C. What is happening in your life?
D. You are lucky.
【单选题】
— Do you mind my smoking here?___
A. No, thanks.
B. Yes, I do.
C. Yes. I'd rather not.
D. Good idea.
【单选题】
— Did you know that David injured his leg yesterday?Really? ___
A. Who did that?
B. What's wrong with him?
C. How did that happen?
D. Why was he so careless?
【单选题】
— This box is too heavy for me to carry it upstairs.___
A. You may ask for help.
B. I'll give you a hand.
C. Please do me a favor.
D. I'd come to help.
【单选题】
— I wonder if I could use your computer tonight?___ I'm not using it right now.
A. Sure, here you are.
B. I don't know.
C. It doesn't matter.
D. Who cares?
【单选题】
— Excuse me, could you show me the way to the nearest post office?___ Oh yes! Two blocks away from here at the Green Avenue. You can’t miss it.
A. I beg your pardon?
B. What do you mean?
C. You’re welcome.
D. Um, let me think.
【单选题】
— Wow! This is a marvelous room! I’ve never known you’re so artistic.____
A. Great, I am very art-conscious.
B. Don’t mention it.
C. Thanks for your compliments.
D. It's fine.
【单选题】
— Is it possible for you to work late tonight？___
A. I like it.
B. I'll do that.
C. I'd love to. .
D. I think so.
【单选题】
— Unbelievable! I have failed the driving test again!___ This is not the end of the world.
A. Good luck.
B.
C. heer up. C. Go ahead.
D. No problem.
【单选题】
Are you feeling better today, Jack?___
A. There must be something wrong.
B. Just have a good rest.
C. Yes, thank you, doctor. But I still don't feel good.
D. Don’t worry about me.
【单选题】
Thank you so much for your lovely gift.___
A. Never mind.
B. I'm glad you like it.
C. Please don't say so.
D. No, It's not so good.
【单选题】
Would you like something to drink? What about a cup of tea?___
A. No, thanks.
B. No, I wouldn’t
C. Yes, I want.
D. Yes, I like.
【单选题】
What's the problem with your bike?___
A. Not at all.
B. Good, thank you.
C. Nothing serious.
D. Sure.
【单选题】
Good morning, John. How are you doing?___
A. I'm pleased
B. Good night.
C. Not so bad. And you?
D. How do you do?
【单选题】
How do you do?___
A. Fine, thank you.
B. How do you do?
C. Not too bad.
D. Very well.
【单选题】
Good-bye for now.___
A. The same to you.
B. That's OK
C. See you.
D. Long time no see.
【单选题】
Hello, how are you?___
A. Hello, how are you?
B. How do you do?
C. Fine, thank you.
D. That's OK.
【单选题】
I didn't mean to do that. Please forgive me。___
A. Not too bad.
B. That's all right
C. It's a pleasure.
D. Thank you.
【单选题】
Thank you for your invitation.___
A. It doesn’t matter.
B. It's a pleasure.
C. It's a small thing.
D. I'll appreciate it.
【单选题】
What a beautiful dress you have on today!___
A. It is suitable for me.
B. No, it isn’t.
C. You want to have one, too?
D. Thank you.
【单选题】
I think he is a good lecturer.___
A. Sorry, it doesn’t matter.
B. So do I.
C. Yes. It's a good idea
D. I don't mind
【单选题】
— What's the matter, dear?___
A. I didn't go to school.
B. I have a terrible headache.
C. I took the kids shopping today.
D. It is a beautiful dress.
推荐试题
【单选题】
4下列半导体材料哪一种的热敏性突出“导电性受温度影响最大”？___
A. 本征半导体
B. N型半导体质
C. P型半导体
【单选题】
5用万用表电阻挡检测某一个二极管时，发现其正、反电阻均近于1000KΩ，这说明该二极管是属于___。
A. 短路状态；
B. 完好状态；
C. 断路状态；
D. 极性搞错。
【单选题】
6稳压二极管是一个可逆击穿二极管，稳压时工作在___状态。
【单选题】
7三端集成稳压器CW7812的输出电压是___。
【单选题】
8三端集成稳压器CXX7805的输出电压是___
【单选题】
9一个平衡PN结，用导线将P区和N区连起来，而导线中___。
A. 有微弱电流
B. 无电流
C. 有瞬间微弱电流
【单选题】
10二极管两端正向电压大于___电压时，二极管才导通。
【单选题】
11当温度升高时，二极管的反向饱和电流 ___ 。
A. 增大；
B. 减小；
C. 不变；
D. 无法判定。
【单选题】
12硅二极管的正向导通压降比锗二极管的___ 。
【单选题】
13三端集成稳压器 CW7906的输出电压是___
【单选题】
14稳压管的工作是利用伏安特性中的___。
A. 正向特性
B. 反向特性
C. 反向击穿特性
【单选题】
15二极管具有___
A. 正向特性
B. 反向特性
C. 单向导电特性
D. 反向击穿特性
【单选题】
16图中D1-D3为理想二极管，A，B，C灯都相同，试问___灯最亮。
【单选题】
18在单相桥式整流电容滤波电路中，设U2为其输入电压，输出电压的平均值约为___。
A. U0=0.45U2
B. U0=1.2U2
C. U0=0.9U2
D. U0=1.4U2
【单选题】
19在单相桥式整流电路中，设U2为其输入电压，输出电压的平均值约为___。
A. U0=0.45U2
B. U0=1.2U2
C. U0=0.9U2
D. U0=1.4U2
【单选题】
20在半波整流电容滤波电路中，设U2为其输入电压，输出电压的平均值约为___。
A. U0=0.45U2
B. U0=1.2U2
C. U0=0.9U2
D. U0=1.4U2
【单选题】
21在半波整流电路中，设U2为其输入电压，输出电压的平均值约为___。
A. U0=0.45U2
B. U0=1.2U2
C. U0=0.9U2
D. U0=1.4U2
【单选题】
22温度影响了放大电路中的___，从而使静态工作点不稳定。
A. 电阻；
B. 电容；
C. 三极管；
D. 电源。
【单选题】
23用直流电压表测得放大电路中某三极管各极电位分别是2V、6V、2.7V，则三个电极分别是___。
A. [B、C、E]
B. [C、B、E]
C. [E、C、B]
【单选题】
24共射极放大电路的交流输出波形上半周失真时为___
【单选题】
25三极管的反向电流ICBO是由___组成的。
A. 多数载流子
B. 少数载流子
C. 多数载流子和少数载流子
【单选题】
27如果在NPN型三极管放大电路中测得发射结为正向偏置，集电结也为正向偏置，则此管的工作状态为___
A. 放大状态；
B. 截止状态；
C. 饱和状态；
D. 不能确定。
【单选题】
28在以下三种电路中输入电阻最大的电路是___。
A. 共基放大电路
B. 共集放大电路
C. 共射放大电路
【单选题】
29在以下三种电路中既能放大电流，又能放大电压的电路是___。
A. 共基放大电路
B. 共集放大电路
C. 共射放大电路
【单选题】
30在以下三种电路中输出电阻最小的电路是___；
A. 共基放大电路
B. 共集放大电路
C. 共射放大电路
【单选题】
当PNP型晶体管工作在放大区时，各极电位关系为uC ___uB。
【单选题】
32当PNP型晶体管工作在放大区时，各极电位关系为uB___uE 。
【单选题】
33测得NPN型三极管上各电极对地电位分别为，，，说明此三极管处在___。
A. 放大区
B. 饱和区
C. 截止区
D. 反向击穿区
【单选题】
34若使三极管具有电流放大能力，必须满足的外部条件是___。
A. 发射结正偏、集电结正偏
B. 发射结反偏、集电结反偏
C. 发射结正偏、集电结反偏
D. 发射结反偏、集电结正偏
【单选题】
35在由PNP晶体管组成的基本共射放大电路中，当输入信号为1KHz、5mV的正弦电压时，输出电压波形出现了顶部削平的失真。这种失真是___ 。
A. 饱和失真
B. 截止失真
C. 交越失真
D. 频率失真
【单选题】
36在由PNP晶体管组成的基本共射放大电路中，当输入信号为1KHz、5mV的正弦电压时，输出电压波形出现了底部削平的失真。这种失真是___ 。
A. 饱和失真
B. 截止失真
C. 交越失真
D. 频率失真
【单选题】
37共集电极放大电路中Re的负反馈组态是___。
A. 电压串联负反馈
B. 电流串联负反馈
C. 电压并联负反馈
【单选题】
38为了使放大器带负载能力强，一般引入___负反馈。
【单选题】
41为了提高三极管放大电路的输入电阻，采用___负反馈 i=i1+i2
【单选题】
42为了稳定输出电流，采用___负反馈。
【单选题】
43为了改善放大器的动态性能，应该引入___电路。
A. 直流负反馈
B. 交流负反馈
C. 电压负反馈
D. 电流负反馈
【单选题】
44为了稳定放大器的静态工作点，应该引入___电路。
A. 直流负反馈
B. 交流负反馈
C. 电压负反馈
D. 电流负反馈
【单选题】
45共模抑制比是差分放大电路的一个主要技术指标，它反映放大电路___能力。
A. 放大差模抑制共模
B. 输入电阻高
C. 输出电阻低
【单选题】
46差分放大电路是为了___而设置的。
A. 稳定Au
B. 放大信号
C. 抑制零点漂移
【单选题】
47分析运放的“虚短”是指是___。
A. U-≈U+
B. I-≈I+≈0
C. U0=Ui
D. U-≈U+≈0
