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【简答题】
在一个工作循环内，曲轴旋转两、活塞往复四个行程，称为（）发动机。
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皮皮学刷刷变学霸
举一反三
【单选题】The field of medicine has always attracted its share of quacks and charlatans—disreputable women and men with little or no medical knowledge who promise quick cures at cheap prices. The reasons why qu...
A.
has a special ability
B.
has little knowledge
C.
is not a good doctor
D.
pretends to be a doctor
【简答题】Russia celebrated
【简答题】论述鱼类转基因目前存在的问题。
【单选题】Which of the following can be inferred about Russia?
A.
Russia needed to compete with other European countries in EMS.
B.
There were no private courier services in Russia.
C.
The postal administration in Russia linked with the network long ago.
D.
Russia was quite hesitant in the international cooperation.
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