Don't waste time or effort worrying about this sort of thing.

Let's stop wasting our time and effort on going down this road to ruin.

He did not waste effort asking the team leader questions.

Why would I waste the time and effort to do that?

But then he seemed to think better of wasting so much effort.

I don't perceive a need to waste time and effort.

"I think it's a shame to waste all their hard work and effort."

They won't waste much effort trying to find an escape route.

But the oil companies have other issues that are much more important to them, and they waste little effort on the ethanol question.

"Why did you waste my time and effort on things you already knew?"