It was a simple matter of focusing his mental energy on useful tasks.

Spock judged that a useful task, a much better use of his time and mental energy than human worry.

At least it would keep her busy with a useful task.

But you did two useful tasks this week, and you've done a really fine job.

The Society enabled youth to express themselves while participating in useful tasks.

"I employ people to do useful tasks such as keeping the press away from me."

I hope to get them to perform useful tasks someday.

We have no problems filling our days with useful and necessary tasks.

He had more useful tasks planned for the robot, in any case.

It costs a great deal to train human beings for useful tasks.