We must do it whole-heartedly, not half-heartedly.

我们要全心全意地做这件事，而不是半心半意。

《新英汉大辞典》

This matter is immediate, we must do it now.

这事刻不容缓，我们必须现在做。

youdao

We must do it.

我们必须这样做。

youdao

"They are right. Of course we must do that. It is a scandal in particular that they still lack enough helicopters to move around in southern Afghanistan.

VOA: standard.2009.07.13

But we must do it in a manner that's consistent with our shared values.

WHITEHOUSE: VP's Remarks to London Cyberspace Conference

"I would think it would be very surprising if a lot of people have been mentioned didn't face action, but we must do it by due process, " he said.

BBC: Graft probe names top Kenyan officials

And we must do it now.

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