网友您好， 请在下方输入框内输入要搜索的题目：
题目内容
（请给出正确答案）
单选题
Even though relatively _____, the diesel engine is highly efficient and needs little servicing.
A
extremely
B
gracefully
C
costly
D
awfully
参考答案
参考解析
解析：
句意：虽然价格很昂贵，但是这种柴油发动机的效能非常高并且很少需要维修。costly高价的，昂贵的。extremely非常地；极端地。gracefully温文地。awfully非常，十分。
句意：虽然价格很昂贵，但是这种柴油发动机的效能非常高并且很少需要维修。costly高价的，昂贵的。extremely非常地；极端地。gracefully温文地。awfully非常，十分。
更多 “单选题Even though relatively _____, the diesel engine is highly efficient and needs little servicing.A extremelyB gracefullyC costlyD awfully” 相关考题
考题
It looks _______ everyone else has gone home.
(A)as though(B) even though(C) even if(D) though
考题
单选题The marine diesel engine is a type of diesel engine used on ships The （） of its operation is not very difficult to understand.A
principleB
principalC
causeD
case
考题
单选题Diesel oil may be used to cool （） of a diesel engine.A
cylindersB
exhaust valvesC
pistonsD
fuel valves
考题
单选题As a heat engine,（） energy is the source of power by which the diesel engine can be operated.A
electricB
heatC
mechanicalD
exhaust
考题
单选题A supercharged diesel engine when compared to a similar naturally aspirated diesel engine, will develop an increase in （）A
ignition lagB
engine horsepowerC
lube oil system pressureD
specific fuel consumption
考题
单选题Gear-type flexible couplings are often used in diesel engine drive trains because they（）A
require no lubrication under normal operating conditionsB
compensate for gross misalignment in the drive trainC
are able to transmit high torque ,even where slight misalignment existsD
will rapidly disconnect the engine from the line shaft
考题
单选题If a diesel engine starts firing, but is unable to come up normal speed, either without load or even under a small load, the cause may be （）A
insufficient fuel supplyB
faulty governorC
high exhaust back pressureD
all of the above may cause this problem
考题
单选题Leaking oil seals on a diesel engine turbocharger can cause（）A
the engine to run after the fuel has been securedB
the engine to over-speedC
a fireD
all of the above
考题
单选题Starting a large low-speed propulsion diesel engine on diesel fuel during cold weather conditions, will be made easier by （）A
increasing the quantity of starting airB
increasing the lube oil pressureC
heating the engine fuel supplyD
heating the engine coolant
考题
单选题Which of the listed diesel engine operating conditions should be checked immediately after any diesel engine is started?（）A
Exhaust temperatureB
Lube oil levelC
Lube oil pressureD
Water level in the expansion tank
考题
单选题In a medium speed diesel engine, a trunk type piston may be cooled by（） Ⅰ.oil circulation though passages in the piston crown Ⅱ.heat transfer through piston rings and liner wallA
Ⅰ onlyB
Ⅱ onlyC
either Ⅰ or ⅡD
neither Ⅰ or Ⅱ
考题
单选题The size of the exhaust valve opening is （）A
most critical in a four-stroke cycle diesel engineB
most critical in a two-stroke/cycle diesel engineC
most critical in a four-stroke/cycle diesel engine if it is turbochargedD
of equal importance in a two-stroke/cycle diesel engine as in a four-stroke/cycle diesel engine
考题
单选题Why a gearbox is needed in a ship driven by a medium-speed diesel engine?（）A
To reduce the main engine speedB
To increase the main engine speedC
To govern the main engine speedD
To fix the propeller shaft
考题
单选题A diesel engine is similar to a gasoline engine except that the former has no （）.A
cross-headB
cylinderC
connecting rodD
spark plug
考题
单选题Proper lubrication of the main bearing is more easily obtained in a single acting four-stroke/cycle diesel engine than in a single acting two-stroke/cycle diesel engine because （）A
bearing pressure in a four-stroke/cycle acting single diesel engine is continually reversedB
bearing pressure in a two-stroke/cycle single acting diesel engine is continually reversedC
the maximum bearing pressure is higher in a single acting two-stroke/cycle diesel engineD
two-stoke/cycle diesel engines require more complicated lubrication piping
考题
单选题What is the effect of heated intake air on a diesel engine? （）A
Increases efficiencyB
Increases engine horsepowerC
Increases engine lifeD
Reduces engine horsepower
考题
单选题In a modern internal combustion diesel engine, the load carrying part of the engine is referred to as the（）A
bedplate or baseB
sump or oil panC
cylinder blockD
frame
考题
单选题Maximum horsepower of a diesel engine is attained （）.A
when the engine RPM is pulled down by overloadB
at rated engine RPMC
at 95 % of rated engine RPMD
at 95 % of a properly adjusted governor RPM with the engine under full load
考题
单选题A two-stroke/cycle diesel engine requires less starting air than a four-stroke/cycle diesel engine, of equal displacement, because the two-stroke/cycle diesel engine（）A
has little or no internal frictionB
has a lower effective compression ratioC
operates with scavenge air under a positive pressureD
operates without energy absorbing intake and exhaust strokes
考题
单选题Significant retardation of a diesel engine fuel injection timing will result in （）A
smoother engine operationB
advanced fuel ignitionC
increased fuel economyD
reduced engine power
考题
单选题What causes diesel fuel to be ignited in the cylinder of an operating diesel engine?（）A
Spark plugB
Heat of compressionC
CarburetorD
Glow plug
考题
单选题For a given size engine, the two-stroke/cycle diesel engine will deliver more power than a four-stroke/cycle diesel engine because （）.A
it has a longer power strokeB
more air gets into the cylinder each strokeC
it develops twice as many power strokes at the same speedD
higher combustion pressure is developed
考题
单选题According to the relevant regulation, lifeboat should be powered by（）.A
inboard diesel engineB
outboard diesel engineC
outboard gasoline engineD
inboard gasoline engine
考题
单选题Fuel oil injected into the cylinder of a diesel engine just after the piston passes top dead center, will（）A
increase engine powerB
increase engine loadC
decrease engine powerD
improve fuel economy
考题
单选题The diesel engine is a type of （）.A
turbine engineB
gas turbineC
steam engineD
internal combustion engine
考题
单选题“This increase in charge air density is accomplished on most modern diesel engine types by use of exhaust gas turbo-charging, in which a turbine wheel driven by exhaust from the engine is rigidly coupled to a centrifugal type air compressor” According to this sentence, we can know that increases density（）, drives the compressor directly（）A
a modern diesel engine；a turbine wheelB
a modem diesel engine；exhaust gasesC
a compressor；an exhaust gas turbochargerD
a compressor；a turbine wheel
考题
单选题Compared to a naturally aspirated diesel engine, a supercharged diesel engine has（）A
a cylinder air charge of higher pressureB
increased pumping lossesC
less valve overlapD
reduced blow-by
热门标签
最新试卷