【单选题】
(30995)露天工作场所遇有___以上大风时禁止高空作业。
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【单选题】
(30996)CAD软件可用来绘制___。
A. 机械零件图
B. 建筑设计图
C. 服装设计图
D. 以上都对
【单选题】
(30997)在使用GAC调速装置的康明斯发电车中,当运行中需换机或并车供电时,可以使用___来实现自动并车。
A. ESD5520
B. LSM201
C. SYC6714
D. 501K
【单选题】
(30998)发电车两机并车所需满足的条件是___。
A. 两机电频率相同
B. 两机电压值相同
C. 两机初相位相同
D. 以上都是
【单选题】
(30999)实现发电机组并车同期方式分为准同期和自同期两种,以下在叙述中不正确的是___。
A. 准同期指发电机并网前已励磁
B. 自同期法是指发电机并网后励磁
C. 自同期法并网速度快
D. 准同期法并网速度比自同期法快
【单选题】
(31000)发电机准同期法并车时常采用灯光并列法,康明斯发电车中采用___。
A. 灯光熄灭法
B. 灯光旋转法
C. 灯光交换法
D. 灯光不灭法
【单选题】
(31001)康明斯KTA-19G2柴油机的喷油器柱塞行程为___。
A. 7.72 mm
B. 7.69 mm
C. 7.36 mm
D. 7.81 mm
【单选题】
(31002)EFC电子调速器上转速降调整旋钮能调整转速降的范围是___。
A. 0~5%
B. 1%~3%
C. 2%~5%
D. 2%~3%
【单选题】
(31003)柱塞式喷油器开始喷油时的喷油压力取决于___。
A. 高压油腔中的燃油压力
B. 调压弹簧的预紧力
C. 喷油器的喷孔数
D. 喷油器的喷孔大小
【单选题】
(31004)康明斯KTA-19G2柴油机的喷油器柱塞是利用___冷却。
【单选题】
(31005)康明斯KTA-19G2柴油机的PT喷油器在喷完燃油后柱塞___。
A. 立即上升
B. 缓慢上升
C. 一直压于杯底
D. 较长一段时间压于杯底
【单选题】
(31006)康明斯发电车的冷却风机自动开启停控制器的控制温度分别是___。
A. 85 ℃,65 ℃
B. 90 ℃,75 ℃
C. 85 ℃,70 ℃
D. 80 ℃,60 ℃
【单选题】
(31007)康明斯发电车中,冷却风机高速电路中的热保护继电器的整定值为___。
A. 32 A
B. 38 A
C. 40 A
D. 45 A
【单选题】
(31008)发电车电气控制原理图中电压互感器文字符号用___标志。
【单选题】
(31009)中间继电器KA和接触器KM的最大区别是___。
A. KA用于直流控制,KM用于交流控制
B. KA用于交流控制,KM用于直流控制
C. KM中一般存在主触头和辅助触头之分,KA中没有主辅触头
D. KA中一般存在主触头和辅助触头之分,KM中没有主辅触头
【单选题】
(31010)画放大电路的交流通道时,电容和直流电源可分别认为是___。
A. 开路,短路
B. 短路,开路
C. 开路,开路
D. 短路,短路
【单选题】
(31011)圆柱度误差是指___。
A. 气缸中垂直于气缸轴线的同一截面上,所测得最大直径与最小直径差值之半
B. 气缸中垂直于气缸轴线的两个截面上,所测得最大直径与最小直径差值之半
C. 气缸中垂直于气缸轴线的同一截面上,所测得最大半径与最小半径差值之半
D. 气缸中垂直于气缸轴线的两个截面上,所测得最大半径与最小半径差值之半请输入内容
【单选题】
(31012)基本偏差为一定的轴的公差带,与不同基本偏差的孔的公差带形成各种配合的一种制度叫___。
A. 基轴制
B. 基孔制
C. 基准制
D. 其它三项所述都不是
【单选题】
(31013)对偏差与公差之关系,下列说法正确的是___。
A. 实际偏差逾大,公差逾大
B. 上偏差逾大,公差逾大
C. 上、下偏差逾大,公差逾大
D. 上、下偏差之差的绝对值逾大,公差逾大
【单选题】
(31014)关于零件草图,下面说法中,正确的是___。
A. 零件草图用徒手目测绘制而成
B. 零件草图的尺寸标准不必齐全
C. 一个零件表达方式,其确定原则是读图方便
D. 零件的破坏损缺陷必须再草图上画出
【单选题】
(31015)机械图样中,标准圆角R8 max 的表示意义是___。
A. 此圆角最大8 mm,最小为0 mm
B. 此圆角最大8 mm,最小不限制
C. 此圆角最小8 mm,最大不限制
D. 此圆角只能为8 mm,不能加大也不能缩小
【单选题】
(31016)基本偏差是___。
A. 上偏差
B. 下偏差
C. 上偏差和下偏差
D. 上偏差或下偏差
【单选题】
(31017)最大极限尺寸___基本尺寸。
A. 大于
B. 小于
C. 等于
D. 大于、小于或等于
【单选题】
(31018)滚动轴承内径尺寸公差的___。
A. 上偏差为负值
B. 下偏差为负值
C. 下偏差为正值
D. 上偏差为正值
【单选题】
(31019)互换性的零件应是___。
A. 相同规格的零件
B. 不同规格的零件
C. 相互配合的零件的零件
D. 具有相同公差的零件
【单选题】
(31020)交流电路测量和自动保护中,使用电流互感器的目的是___。
A. 既可扩大量程,又可降低测量设备及保护设备的绝缘等级
B. 为了安全
C. 为了扩大量程
D. 增加测量保护精度请输入内容
【单选题】
(31021)在三相四线制电路的中线上,不准安装开关和熔断器的原因是___。
A. 中线上没有电流
B. 开关接通或断开对电路无影响
C. 安装开关和熔断器会降低中线的机械强度
D. 开关断开或熔断器熔断后,三相不对称负载承受三相不对称电压的作用,无法正常工作,严重时会烧毁负载
【单选题】
(31022)使用电流互感器和电压互感器时,其二次绕组应分别___接入被测电路之中。
A. 串联、并联
B. 并联、串联
C. 串联、串联
D. 并联、并联
【单选题】
(31023)零件测绘时,被测要素遵守___原则时,其实际形状遵守的理想边界为最大实体边界。
A. 最大实体
B. 最小实体
C. 包容
D. 独立
【单选题】
(31024)同一组蓄电池中各个蓄电池的容量互差不得超过___。
A. 5%
B. 10%
C. 15%
D. 20%
【单选题】
(31025)气门间隙过小不会引起___。
A. 影响进、排气门的启闭定时
B. 发动机最大功率下降
C. 柴油机发出强烈的噪声
D. 压缩时漏气,压缩终点压力、温度降低
【单选题】
(31026)康明斯KTA-19G2柴油机进气推杆顶弯将会造成___。
A. 气门关闭不严
B. 进气门间隙偏大
C. 进气摇臂受力增大
D. 其它三项所述都不对
【单选题】
(31027)发动机气门间隙过大,使气门脚发出异响,可用___进行辅助判断。
【单选题】
(31028)KTA-19G2型柴油机进排气门间隙分别是___。
A. 0.3 mm,0.35 mm
B. 0.35 mm,0.35 mm
C. 0.35 mm,0.40 mm
D. 0.36 mm,0.69 mm
【单选题】
(31029)在调整康明斯KTA-19G2柴油机气门间隙时,若指示标志C对准最高点时,要调整___全部气门间隙。
A. 1缸或6缸
B. 2缸或5缸
C. 3缸或4缸
D. 2缸和5缸
【单选题】
(31030)用千分表法调整康明斯KTA-19G2柴油机喷油器柱塞行程时,若5号缸可以调气门间隙,则___可以调喷油器柱塞行程。
【单选题】
(31031)发动机气门间隙调整可分为热调和冷调,其中冷调是指发动机机不工作至少4 h或水温油温不超过___ 时调整。
A. 90 ℃
B. 85 ℃
C. 65 ℃
D. 60 ℃
【单选题】
(31032)康明斯KTA-19G2柴油机中,顺时针拧动喷油器塞调整螺钉,将使相应的喷油器柱塞行程___。
A. 变大
B. 变小
C. 不变
D. 变大或变小
【单选题】
(31033)若康明斯KTA-19G2柴油机中使用的PT喷油器上部密封圈损坏将造成___。
A. 每循环喷油量下降
B. 喷油压力变大
C. 喷油雾化不良
D. 其它三项所述都不对
【单选题】
(31034)康明斯KTA-19G2柴油机中使用的PT喷油器工作时绝大多数时间是处于___阶段。
A. 量油
B. 喷油
C. 旁通回油
D. 预喷
【单选题】
(31035)康明斯KTA-19G2柴油机的喷油器柱塞行程若调整偏大,将造成___。
A. 喷油器积炭
B. 摇臂折断
C. 供油推杆弯曲
D. 其它三项所述都可能
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【单选题】
25. The boy_____ a yellow sweater can_____ himself now.
A. wearing; dress B. putting on; wear C. put on; dress D. dressing;
【单选题】
( ) 26. Where does the writer of "The little Prince" come from?
A.England. B.France. C.America. D.China.
【单选题】
( ) 27. What does the prince do after the fox tells him a secret?
A.He cares more about a flower and a sheep.
B.He meets many more strange adults on other planets.
C.He realizes his love for the rose and he goes back to his planet.
D.He discovers interesting things such as a snake, other roses and a fox.
【单选题】
( ) 28. What does "The little Prince" mainly talk about? It' s about _________.
A.the adult world B.the planet B -612
C.a rose and a fox D.the adventure of a young
【单选题】
( ) 29. When a baseball player hits the ball, he must ______ to get a point.
A. run to each base freely
B. touch the home plate first
C. touch all the bases with his hands
D. run to each base in order and touch it with his foot
【单选题】
( ) 30. When was the importance of touching all the bases shown?
A. Before the baseball rules made.
B. At the end of the 1974 baseball seasons.
C. At the start of the 1974 baseball seasons.
D. In the second week of 1974.
【单选题】
( ) 31. Who hit home run number 715?
A. Babe Ruth. B. Hank Aaron. C. Babe Ruth’s partner. D. Hank Aaron’s friend.
【单选题】
( ) 32. What does the expression “to touch all bases” mean?
A. To try your best to set a new record.
B. To get a chance to be the greatest hitter.
C. To do what is needed to finish an activity.
D. To solve the problems successfully.
【单选题】
( ) 33. The Chinese Yellow Sea Wetlands are in the _______ of China.
A.south B.east C.west D.north
【单选题】
( ) 34. Usually the weather in the wetlands is _______.
A.hot B.pleasant C.cold D.dry
【单选题】
( ) 35. The World Wetlands Day is on _______.
A.February 2 B.June 25 C.April 22 D.March 22
【单选题】
( ) 36. We must protect wetlands because _______.
A.they are home for wildlife B.they can prevent flood
C.they can offer food to the animals and birds D.all of the above
【单选题】
( ) 37.The greatest river for navigation is ___________.
A. the Nile B. the Amazon C. the Mekong D. the Mississippi
【单选题】
( ) 38. From a dam, people can use the water for ___________.
A. keeping the rivers clean B. only making electricity
C. irrigation and making electricity D. washing clothes
【单选题】
( ) 39. The water in the river is polluted because of _____________.
A. people's drinking water too much B. people's swimming in the river too much
C. chemicals and other materials D. people's building a dam across a river
【单选题】
( ) 40. The best title of the passage is ___________.
A. Rivers in Cities B. The importance of Rivers
C. Transportation D. Natural Resources
【单选题】
1.—Hello! This is Henry Speaking.I’d like to speak to your father.
—Sorry, he has Shanghai.
A. been in B. been to C. come to D. gone to
【单选题】
2. — It’s difficult for the village children to cross the river for school.
— I think a bridge ______ over the river.
A. was built B. is being built C. has been built D. should be built
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3. —Where would you like to go, Jinan or Qufu?
— .I only want to go to Qingdao.
A. Each B. Either C. Neither D. All
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4. — The documentary A Bite Of China II is quite popular around China recently. How do you like it? — ______.
A. I think so B. Pretty good C. It’s my pleasure D. All right
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5. There are three English-books on the shelf, but ______ of them is mine.
A. both B. neither C.all D. none
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6. When the parents arrived at the hall, the students _______ their projects.
A. have finish B. finished C. had finished D. are finishing
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7. This week, the _______ seems to change every day: one day is hot; the next day is cold.
A. time B. weather C. season D. way
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8. He never does his work _______ Mary.
A. as careful as B. so careful as C. carefully as D. as carefully as
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9. — Can he jump high?
— Yes, he ______. He is a good high jumper.
A. must B. need C. can D. shall
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10. The shop _____ at 8:00 a.m.and it ________ for ten hours every day.
A. is open; has opened B. is opened; opens
C. opens; is open D. opened; opens
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11. —Excuse me, may I use your bicycle? ______ is broken.
—Certainly. But remember to return it before lunch.
A. Mine B. Me C. Myself D. I
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12. —Simon, what do I need to take for the hiking?
—You’d better ________ more water than usual. It’s hot today.
A. to take B. taking C. take D. took
【单选题】
13. Helen ______ to a language school when she was seven.
A. sent B. is sent C. will send D. was sent
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14. — Is this park you’ve visited recently?
— Yes, it's the most beautiful one I’ve ever visited before.
A. that B. the one C. which D. the one which
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15. — It’s difficult for the village children to cross the river for school.
— I think a bridge ________ over the river.
A. should be built B. is being built C. has been built D. was built
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16. — Could you tell me when Mr. Li ________ in Huaibei?
— Sure..When he ________, I’ll call you.
A. arrives; will arrive B. will arrive; will arrive
C. arrives; arrives D. will arrive; arrives
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) 17.There is ________ 800-metre-long road behind ________ hospital.
A. an; an B. an; the C. a; a D. a; the
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18. — Did you see a girl in yellow pass by just now?
— No, sir. I ________ a magazine.
A. read B. am reading C. was reading D. would read
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19.In fact, my parents are not only kind to me, but also strict ________ me.
A. at B. to C. for D. with
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20. The boy_____ a yellow sweater can_____ himself now.
A. wearing; dress B. putting on; wear C. put on; dress D. dressing; wear
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21. —Jack, I haven’t seen your brother for a long time.
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22. The meat with eggs tastes ______. Would you like some more?
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23. — Look! The man standing at the gate ______ be our headmaster.
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24. The Japanese government must do everything ________ polluted water from running into rivers, lakes, seas and oceans.
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