【单选题】
89S51比89C51多出了哪个功能？___
A. 存储器加倍
B. 具有WDT工能
C. 多了一个8位输入/输出端口
D. 多了一个串行口
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答案
B
解析
暂无解析
相关试题
【单选题】
24在8×51的程序里，若要将某个输入/输出端口设置成输入功能，应如何处理？___
A. 先输出高电平到该输入/输出端口
B. 先输出低电平到该输入/输出端口
C. 先读取该输入/输出端口的状态
D. 先保存该输入/输出端口的状态
【单选题】
29在Keil µVision3里进行调试/仿真时，在哪里操作才能触动程序中断？___
A. 在Interrupt System
B. 在Cotorl Box对话框里
C. 直接单击魔术棒按钮即可
D. 直接按0键
【单选题】
36在12MHz的8×51系统里，哪一种方式一次可定时5ms？___
A. Mode 0及Mode 1
B. Mode 1及Mode 2
C. Mode 2及Mode 3
D. Mode3及Mode 1
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【单选题】
Q1: What does the man suggest that the woman do this weekend?___
A. Read J .K .Rowling's first book .
B. Go to buy a new Harry Potter book .
C. Watch BBC news about J .K .Rowling .
D. Take her cousin to see a new Harry Potter movie .
【单选题】
Q2: Where did J. K. Rowling come up with the idea for Harry Potter?___
A. At a cafe .
B. On a train .
C. At a cinema .
D. In a bookstore .
【单选题】
Q3: What are J. K. Rowling’s future plans?___
A. She won't write any more books .
B. She will write more magic stories .
C. She hasn't said anything about her future plans .
D. She said she would work on more serious subjects .
【单选题】
Q4: What are the two speakers mainly talking about?___
A. J.K. Rowling's secret .
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C. A new book by J .K.Rowling.
D. An interview with J .K .Rowling .
【单选题】
Q1: What happened when Stephen tried to remove a bottle of milk from the refrigerator?___
A. He broke the milk bottle .
B. He fell down on the floor .
C. He made a mess inside the refrigerator .
D. He spilled the milk over the kitchen floor .
【单选题】
Q2: What did Stephen’s mother do when she came into the kitchen？___
A. She gave him a long lecture .
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C. She enjoyed the wonderful mess .
D. She cleaned up the mess with him .
【单选题】
Q3: What did Stephen’s mother teach him later?___
A. How to do an experiment .
B. How to carry a milk bottle .
C. How to clean up spilled milk .
D. How to avoid making mistakes .
【单选题】
Q4: What did Stephen learn from this experience?___
A. Mistakes can become learning opportunities .
B. Mistakes are just like scientific experiments .
C. One should sometimes make mistakes .
D. One should try to avoid making mistakes .
【单选题】
Q1: Why is surfing the man’s favorite activity?___
A. Because he likes the sunny weather.
B. Because he wants to challenge himself .
C. Because it can help solve his sleeping problem .
D. Because it can help him forget all his troubles .
【单选题】
Q2: What is the woman going to do this weekend?___
A. To go sailing .
B. To go surfing .
C. To go to the beach .
D. To go to her nephew's .
【单选题】
Q3: What does the woman love doing?___
A. Going to visit relatives.
B. Enjoying the warm sun on the beach .
C. Building sand castles with her niece and nephew .
D. Playing in the sand and jumping in the waves .
【单选题】
Q4: What does the man remember doing with his brothers?___
A. Surfing in the sea .
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【单选题】
Q1: According to the survey, what percentage of British adults watched TV in theirfree time?___
A. 89 percent .
B. 84 percent .
C. 76 percent .
D. 71 percent .
【单选题】
Q2: Which age group would be the most likely to visit their friends and relatives?___
A. People aged 16 to 24
B. People aged 25 to 34 .
C. People aged 16 and over .
D. People aged 55 and over .
【单选题】
Q3: What does the speaker say about listening to music as a leisure activity for British people?___
A. People aged 16 to 24 preferred listening to music most .
B. It was getting more and more popular among the British people .
C. It was the third most popular activity among people aged 55 and over .
D. People aged 25 to 34 listened to music more often than those aged 16 to 24 .
【单选题】
Q4: According to the survey, how are leisure activities related to age?___
A. Older people go out to pubs more often . frequently .
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C. Older people spend more time reading and gardening .
D. Younger people spend less time visiting friends and family .
【单选题】
Q1: Why was the girl excited?___
A. She is going to have a lot of vanilla ice cream .
B. She won the spelling competition at her school .
C. She is going to the state capital for a competition .
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【单选题】
Q2: What happened when the man was 13 years old?___
A. His family moved to Sacramento to settle down .
B. His family bought him a new suit and a new tie .
C. He went to Sacramento for a spelling competition .
D. He won the first prize in the state spelling competition .
【单选题】
Q3: Why did the man’s mom give him a big hug?___
A. To make him feel better after he lost the first prize .
B. To apologize for not buying him some ice cream .
C. To wish him good luck in the next competition .
D. To congratulate him on winning the first prize .
【单选题】
Q4: What color is the girl going to wear for her next competition?___
A. Red .
B. Blue .
C. Green .
D. Yellow .
【单选题】
Q1: What is this passage mainly about?___
A. Superstitions and science .
B. Tips on how to have good luck .
C. Superstitions in the United States .
D. Rational and superstitious societies .
【单选题】
Q2: According to the passage, what is considered as bad luck?___
A. Walking under a ladder .
B. Dreaming of a black cat .
C. Hanging a mirror in the house .
D. Stepping on one's own shadow .
【单选题】
Q3: Why is it considered bad luck to see a black cat crossing one’s path?___
A. Because black cats look like witches . e witches .
B. Because black cats were thought to be witches .
C. Because black cats bring seven years of bad luck .
D. Because black cats are hard to notice in darkness .
【单选题】
Q4: According to the passage, what will bring people good luck?___
A. Breaking a mirror on purpose .
B. Catching a falling leaf on one's birthday .
C. Finding a on the ground and picking it up .
D. Dreaming of blowing out the candles in one blow .
【单选题】
Q1: How long will the woman spend on her way to and from work by high-speed train?___
A. 4 hours .
B. 2 hours .
C. 1.5 hours .
D. 45 minutes .
【单选题】
Q2: When does the woman arrive back home by subway?___
A. At 8 .
B. At 7 .
C. At 6 .
D. At 5 .
【单选题】
Q3: According to the woman, in what way will the new high-speed train be a big help to her?___
A. She can either read or rest a little on the train .
B. She can read and respond to emails onthe train .
C. She can travel to many different parts of the city .
D. She can go shopping on her way home from work .
【单选题】
Q4: How will the new high-speed train affect the man?___
A. He can take the train to the old part of the city .
B. He can save a lot of money when he takes the train .
C. He can save 20 minutes to go to work with the train .
D. He can take the train to the airport instead of driving .
【单选题】
Q1: How much time on average do Americans spend on their way to work?___
A. About an hour .
B. More than an hour .
C. About half an hour .
D. More than one and a half hours .
【单选题】
Q2: What is the present situation about Americans’ commuting to work?___
A. More and more Americans spend over an hour getting to work .
B. Over 10 percent of Americans spend less than an hour getting to work .
C. Only New York people spend more than 90 minutes getting to work .
D. Over 10 percent of Americans spend more than 90 minutes getting to work .
【单选题】
Q3: Why does Steven choose to have an extreme commute?___
A. Because gas prices are not high .
B. Because the commute is not tiring .
C. Because he can attend a better school .
D. Because he can have his favorite lifestyle .
【单选题】
Q4: Which of the following is the disadvantage of long commutes?___
A. Traffic jams .
B. Expensive housing .
C. Poorer life quality .
D. A tiring and boring trip .
【单选题】
Q1: What did Katy like about Jason’s last Halloween party?___
A. She liked playing an interesting game .
B. She enjoyed seeing many of her old friends .
C. She enjoyed wearing her Halloween costume .
D. She liked the decorations in Jason's front yard .
【单选题】
Q2: What is the actual reason that Katy doesn’t want to attend Jason’s party?___
A. None of her friends likes Jason .
B. None of Jason's guests is young .
C. She wants to go to Linda's party ..
D. She went to Jason's party last year .
【单选题】
Q3: What is special about Linda’s party?___
A. The party will last four hours .
B. Six people will attend the party .
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【单选题】
Q4: What will Katy do to solve her problem?___
A. Go to Jason's party .
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C. Attend both Jason's and Linda's parties .
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【单选题】
Q1: What is special about this year’s Black Friday shopping?___
A. Some stores offered bigger holiday discounts .
B. Some stores provided more choices of nightlife.
C. Some stores made efforts to attract young people .
D. Some stores opened much earlier than they used to .
【单选题】
Q2: Why did some stores open at midnight on Thanksgiving night?___
A. To attract young customers .
B. To beat other stores for sale.
C. To let people sleep late the next day .
D. To keep people stay up for the night .
【单选题】
Q3: How many Black Friday shoppers were reported to go to the shops at midnight this year?___
A. 24 percent .
B. 37 percent .
C. 9.5 percent .
D. 23.5 percent .
【单选题】
Q4: What can we learn about the 15-year-old Jenny?___
A. She and her cousins went back home at midnight .
B. She liked the traditional 4 a.m. Black Friday.
C. She preferred midnight shopping to early morning shopping .
D. She and her cousins got up very early to buy discounted items .
