Don 't use time or words carelessly. Neither can be retrieved.
不要轻率的使用时间或言辞，因为二者都不可能被收回。
You don "t use your time profitably."
你没有有效利用时间。
If the filament transformer has a center tap, don 't use it.
如果变压器灯丝绕组有抽头，请不要使用它。
Don "t use abbreviations unless you" re quite sure your reader will understand them.
不要使用缩写除非你很确定对方一定能理解。
Don "t use abbreviations unless you" re quite sure your reader will understand them.
不要使用缩写除非你很确定对方一定能理解。
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