单项选择题
When the fuel oil is burning in the combustion chamber, it （）.
A.gives up large amount of heat B.gives off large amount of heat C.gives up large amount of steam D.gives off large amount of steam
单项选择题 After the ship is out of the harbour and in “Full Speed”, well change （）.
单项选择题 A diesel engine burns （） a gasoline engine of the same capacity in the same period of time.
单项选择题 Since the engine doesn’t work well, you’d better （） as soon as possible.
