I didn't want to spook the deer and force them to waste precious energy at the time of year that they could least afford it.

Where only information was important, it was a waste of precious energy to transfer bulk matter.

Hot day like this, it didn't pay to expend precious energy.

"I hope these young professionals are using their precious energy on more important issues," she said.

"Had they been in my keeping, I would not have been required to waste precious energy to speak about them."

I'd used up a lot of precious energy dealing with Curtis.

We have recently installed smart metering that will give more precious energy use.

But he must not waste precious energy worrying about that just now.

Don't waste precious energy trying to convince yourself that nothing's going on.

I have already expended precious energies trying to reach it.