相关试题
【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 .
B. J .K .Rowling's writing plan .
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 .
B. She shouted at him in anger .
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 .
B. Collecting seashells .
C. Building sand castles .
D. Jumping in the waves .
【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 .
B. Younger people go to the cinema less frequently.
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 .
D. She "excellence"correctly,but others didn't .
【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 .
C. They will have huge bags of candy .
D. They will play a new game called "GuessWho ".
【单选题】
Q4: What will Katy do to solve her problem?___
A. Go to Jason's party .
B. Go to Linda's party .
C. Attend both Jason's and Linda's parties .
D. Celebrate Halloween with her parents .
【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 .
推荐试题
【单选题】
金属零件在交变热应力反复作用下遭到破坏的现象称___。
A. 热冲击;
B. 热脆性;
C. 热变形;
D. 热疲劳。
【单选题】
电网频率超出允许范围长时间运行,将使叶片产生___,可造成叶片折断。
A. 裂纹;
B. 松动;
C. 蠕变;
D. 振动。
【单选题】
超速试验时,汽轮机转子应力比额定转速下应力应增加约___的附加应力。
A. 20%;
B. 25%;
C. 30%;
D. 15%。
【单选题】
协调控制系统共有五种运行方式,其中负荷调节反应最快的方式是___。
A. 机炉独自控制方式;
B. 协调控制方式;
C. 汽轮机跟随锅炉方式;
D. 锅炉跟随汽轮机方式。
【单选题】
汽轮发电机组转子的振动情况可由___来描述。
A. 振幅、波形、相位;
B. 位移、位移速度、位移加速度;
C. 激振力性质、激振力频率、激振力强度;
D. 轴承稳定性、轴承刚度、轴瓦振动幅值。
【单选题】
当汽轮发电机组转轴发生动静摩擦时,___。
A. 振动的相位角是不变的;
B. 振动的相位角是变化的;
C. 振动的相位角有时变、有时不变;
D. 振动的相位角始终是负值。
【单选题】
中间再热机组在滑参数减负荷停机过程中,再热蒸汽温度下降有___现象。
A. 超前;
B. 滞后;
C. 相同;
D. 先超后滞。
【单选题】
汽轮发电机组的自激振荡是___。
A. 负阻尼振荡;
B. 有阻尼振荡;
C. 无阻尼振荡;
D. 正阻尼振荡。
【单选题】
发电机同期并列时,它与系统相位差不超过___。
A. ±10°;
B. ±5°;
C. ±20°;
D. ±15°。
【单选题】
电流流过人体,造成对人体的伤害称为___。
A. 电伤;
B. 触电;
C. 电击;
D. 电烙印。
【单选题】
在外界负荷不变的情况下,汽压的稳定主要取决于___。
A. 炉膛热强度的大小;
B. 炉内燃烧工况的稳定;
C. 锅炉的储热能力;
D. 锅炉的型式。
【单选题】
汽轮发电机在启动升速过程中,没有临界共振现象发生的称为___转子。
A. 挠性;
B. 刚性;
C. 重型;
D. 半挠性
【单选题】
径向钻孔泵调节系统中的压力变换器滑阀是___。
A. 断流式滑阀;
B. 继流式滑阀;
C. 混流式滑阀;
D. 顺流式滑阀。
【单选题】
在全液压调节系统中,转速变化的脉冲信号用来驱动调节汽门,是采用___。
A. 直接驱动方式;
B. 机械放大方式;
C. 逐级放大后驱动的方式;
D. 油压放大后驱动的方式。
【单选题】
调节系统的错油门属于___。
A. 混合式滑阀;
B. 顺流式滑阀;
C. 继流式滑阀;
D. 断流式滑阀。
【单选题】
随着某一调节汽门开度的不断增加,其蒸汽的过流速度在有效行程内是___的。
A. 略有变化;
B. 不断增加;
C. 不变;
D. 不断减少。
【单选题】
某台汽轮机在大修时,将其调节系统速度变动率调大,进行甩负荷试验后发现,稳定转速比大修前___。
A. 低;
B. 高;
C. 不变;
D. 略有提高。
【单选题】
同步器改变汽轮机转速的范围一般为额定转速的___。
A. 2%~+5%;
B. 3%~+5%;
C. 4%~+6%;
D. 5%~+7%。
【单选题】
汽轮机启动暖管时,注意调节送汽阀和疏水阀的开度是为了___。
A. 提高金属温度;
B. 减少工质和热量损失;
C. 不使流入管道的蒸汽压力、流量过大,引起管道及其部件受到剧烈的加热;
D. 不使管道超压。
【单选题】
汽轮机热态启动,蒸汽温度一般要求高于调节级上汽缸金属温度50~80℃是为了___。
A. 锅炉燃烧调整方便;
B. 避免转子弯曲;
C. 不使汽轮机发生水冲击;
D. 避免汽缸受冷却而收缩。
【单选题】
当主蒸汽温度和凝汽器真空不变,主蒸汽压力下降时,若保持机组额定负荷不变,则对机组的安全运行___。
A. 有影响;
B. 没有影响;
C. 不利;
D. 有利。
【单选题】
调整抽汽式汽轮机组热负荷突然增加,若各段抽汽压力和主蒸汽流量超过允许值,应___。
A. 手动减小负荷,使监视段压力降至允许值;
B. 减小供热量,开大旋转隔板;
C. 加大旋转隔板,增加凝汽量;
D. 增加负荷,增加供热量。
【单选题】
主蒸汽管的管壁温度监测点设在___。
A. 汽轮机的电动主汽门前;
B. 汽轮机的自动主蒸汽门前;
C. 汽轮机的调节汽门前的主蒸汽管上;
D. 主汽门和调节汽门之间。
【单选题】
圆筒形轴承的顶部间隙是椭圆轴承的___倍。
A. 2;
B. 1.5;
C. 1;
D. 1/2。
【单选题】
对于直流锅炉,在启动过程中,为了避免不合格的工质进入汽轮机并回收工质和热量,必须另设___。
A. 汽轮机旁路系统;
B. 启动旁路系统;
C. 给水旁路系统;
D. 高压加热器旁路系统。
【单选题】
当需要接受中央调度指令参加电网调频时,机组应采用___控制方式。
A. 汽轮机跟随锅炉;
B. 锅炉跟随汽轮机;
C. 汽轮机锅炉手动;
D. 汽轮机锅炉协调。
【单选题】
锅炉跟随汽轮机控制方式的特点是:___。
A. 主蒸汽压力变化平稳;
B. 负荷变化平稳;
C. 负荷变化快,适应性好;
D. 锅炉运行稳定。
【单选题】
表示正弦电路中电容元件容抗的计算式,正确的是___。
A. i=U/(XC);
B. i=U/(C);
C. I=UC;
D. I=U/(C)。
【单选题】
班组加强定额管理工作中的劳动定额是指___。
A. 工时定额、产量定额;
B. 质量定额、产量定额;
C. 成品定额、工时定额;
D. 质量定额、成品定额。
【单选题】
一个标准大气压(1atm)等于___。
A. 110.325kPa;
B. 101.325kPa;
C. 720mmHg;
D. 780mmHg。
【单选题】
班组民主管理不包括___管理。
A. 政治民主;
B. 经济民主;
C. 生产技术民主;
D. 奖惩民主。
【单选题】
运行分析工作不包括___。
A. 安全分析;
B. 定期分析;
C. 岗位分析;
D. 专题分析。
【单选题】
在主蒸汽管道系统中,为防止发生蒸汽温度偏差过大现象,可采取的措施为___。
A. 采用喷水减温的方法;
B. 采用回热加热的方法;
C. 采用中间联络管的方法;
D. 采用减温器的方法。
【单选题】
机组甩负荷时,转子表面产生的热应力为___。
A. 拉应力;
B. 压应力;
C. 交变应力;
D. 不产生应力。
【单选题】
提高蒸汽初温,其他条件不变,汽轮机相对内效率___。
A. 提高;
B. 降低;
C. 不变;
D. 先提高后降低。
【单选题】
中间再热使热经济性得到提高的必要条件是___。
A. 再热附加循环热效率大于基本循环热效率;
B. 再热附加循环热效率小于基本循环热效率;
C. 基本循环热效率必须大于40%;
D. 再热附加循环热效率不能太低。
【单选题】
在汽轮机启动过程中,发生___现象,汽轮机部件可能受到的热冲击最大。
A. 对流换热;
B. 珠状凝结换热;
C. 膜状凝结换热;
D. 辐射换热。
【单选题】
对于一种确定的汽轮机,其转子或汽缸热应力的大小主要取决于___。
A. 蒸汽温度;
B. 蒸汽压力;
C. 机组负荷;
D. 转子或汽缸内温度分布。
【单选题】
选择蒸汽中间再热压力对再热循环热效率的影响是___。
A. 蒸汽中间再热压力越高,循环热效率越高;
B. 蒸汽中间再热压力为某一值时,循环效率最高;
C. 汽轮机最终湿度最小时相应的蒸汽中间压力使循环效率最高;
D. 汽轮机相对内效率最高时相应的蒸汽中间压力使循环效率最高。
【单选题】
回热加热系统理论上最佳给水温度相对应的是___。
A. 回热循环热效率最高;
B. 回热循环绝对内效率最高;
C. 电厂煤耗率最低;
D. 电厂热效率最高。