That is why he spent so much effort trying to find it.

This is a very focused effort, trying to do things right.

It's worth some effort to try to follow what they're doing.

He spent wasted effort trying to get a hold of Young.

"We ask ourselves if it's worth the effort trying to change his mind."

Both sides have wasted a great deal of effort trying to do something that simply could not be done.

Peter knew better than to waste any effort trying to see that fly.

"But if we're not going to be able to get that across, anyway, perhaps we shouldn't waste the effort trying to."

"We're going certainly to continue efforts to try to get people to seek treatment," the Mayor said.

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