Coasting is especially useful if you're driving on country highways and straight roads, where you don't need to floor the accelerator and feed fuel into your engine.
如果你行驶在乡村公路和笔直的道路上，滑行尤其有用，你不用把油门踩到底，也不用给引擎供油。
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Unlike the better balanced straight-six or even the ultra-smooth V-12 engine, the humble four-cylinder generates an up and down vibration with a frequency of twice the crankshaft's rotational speed.