Critics like George Rossman say that is a waste of time.

VOA: standard.2010.07.26

And I am not going to take the time to solve it because I think that is a waste of class time, but those are the three unknowns.

但我并不打算把解这几个方程,我觉得那会是浪费课堂时间，但那是三个未知式。

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I can't help thinking this is a complete waste of time.

我忍不住在想，这完全是在浪费时间。

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