更多"Why shiprepair is an inherently dif"的相关试题:
[单项选择]These plants are rather difficult（）
A. to look after
B. to be looked after
C. being looked after
D. looking after
[单项选择]Wristpin bearings are difficult to lubricate because of their oscillating motion and（）
A. their free-floating design
B. their relatively small size
C. the reciprocating motion of the piston
D. their position in the lubrication system
[单项选择]It is difficult to determine which limb of the Moon is fully illuminated（）.
A. when the Moon is low in the sky at rising or setting
B. at the new Moon phase
C. when taking Moon sights during daylight
D. when the terminator is nearly vertical
[单项选择]If a diesel engine is difficult to start and operates with the engine temperatures lower than normal, you should suspect that the （）.
A. compression pressures are below normal
B. lube oil is diluted with fuel oil
C. cranking speed is too low
D. exhaust system is partially restricted
[单项选择]What do you find difficult in learning English?（）
A. Listening and speaking.
B. Don‘t be afraid of difficulties.
C. Learning English is useful.
D. Don‘t be disappointed.
[单项选择]（）students often find it difficult to live in China at first.
A. Outside
B. Overseas
C. National
D. Abroad
[单项选择]Why are removable sleeves installed on centrifugal pump shafts?（）
A. They make it easier to replace the pump shaft packing
B. They can be economically replaced as they wear out
C. They can be removed when it is necessary to lighten the weight of the pump
D. They increase the strength of the shaft
[单项选择]That was a difficult question, but Mary still（）to work it out.
A. did
B. failed
C. kept
D. managed
[单项选择]This is（）the most difficult job I have ever tackled.
A. by rights
B. by itself
C. by oneself
D. by far
[单项选择]It was difficult to（）how many trees had been destroyed.
A. measure
B. test
C. estimate
D. evaluate
[单项选择]（）she seemed to find English very difficult, but later he made very good progress.
A. At the first
B. At present
C. At the present
D. At first
[单项选择]— The physics exam is not difficult, is it?—（）Even Harry to the top students failed in it.
A. Yes；belongs
B. No；belonged
C. Yes；belonging
D. No；belonging
[判断题]E-Commerce等于E-Business，E-Business活动就是E-Commerce活动。
[单项选择]Why are some diesel engine cylinder liners plated on the wearing surface with porous chromium?（）
A. The chromium will not wear out the piston rings
B. The chromium strengthens the liners in the way of the scavenging air ports
C. Chromium eliminates the need for oil scraper rings
D. Pores in the plating aid in maintaining the lube oil film
[单项选择]Why（）go swimming there?
A. often do you
B. do you often
C. do often you
[多项选择]Why do large OSPF networks use a hierarchical design?（）
A. to confine network instability to single areas of the network.
B. to reduce the complexity of router configuration
C. to speed up convergence
D. to lower costs by replacing routers with distribution layer switches
E. to decrease latency by increasing bandwidth
F. to reduce routing overhead
[单项选择]Why should the SES operators be very careful when the ship enters the area where three ocean regions overlap? Because（）.
A. the weather is always terrible
B. the condition there is complicated
C. the signals are too strong
D. their SES may receive the signals from unwanted satellite
[单项选择]Why is it necessary to extend ventilators of gasoline powered vessels to the bilges（）.
A. To keep them dry，and thus easier to clean
B. To remove fuel vapors which are heavier than air
C. To provide adequate air to the engines
D. To cool the machinery areas
