【判断题】任何情况下都可以设无穷远处为 0 电势点。 ( )
【简答题】Climbing hills__________of great help to health. A.is B.are C.were D.be
【单选题】Climbing hills _____ of great help to health.
【单选题】Climbing hills ______ good for our health.
【简答题】Climbing hills ______ of great help to health. A) is B) are C) were D) be
【单选题】机床电气控制与PLC第1-2章作业.doc
【单选题】Climbing hills()of great help to health.A、isB、areC、wereD、be
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18.Climbing hills()of great help to health. A、is
【判断题】任何情况下都可以设无穷远处为0电势点。( )