单项选择题 It is during （） that work energy is being put into the engine; during the other 3 strokes of the piston, the engine is having to do the work.

单项选择题 In the suction stroke, the crankshaft is rotating clockwise and the piston is moving （） the cylinderThe inlet valve is （） and a fresh charge of air is being drawn or pushed into the cylinder by the turbocharger.

单项选择题 The four-stroke cycle is so called because it takes （） to complete the processes needed to convert the energy in the fuel into work.