It's a waste of time and energy.

那是浪费时间和精力。

《牛津词典》

"It's a waste of time," he concluded.

“这是浪费时间，”他最后说道。

《柯林斯英汉双解大词典》

Personally I think it's a waste of time.

在我看来，我认为这是浪费时间。

《柯林斯英汉双解大词典》

I wouldn't give a midterm, because I think it's a waste of time, except we have to have some sort of-- it gives you an indication how you're doing in the course.

我不想考期中,因为我觉得就是浪费时间,不过我们必须得有点什么,能让你知道你这门课学得怎么样了

耶鲁公开课 - 1871年后的法国课程节选

Getting beat at Wembley is far worse than getting dumped out in the third round as it's a waste of time getting there.

BBC: Kevin Ratcliffe

It's a waste of time for officials to deny that.

CNN: Will Obama's immigration initiative sway Latinos?

If you have a theory that either, you know, is part of your case or part of your defense against charges by the government and there's no legal support for the defense, it's a waste of courtroom time to have a parade of witnesses.

NPR: What Does Watada Case Mean for Military Law?