czas użyteczności

A man could live a good, useful life in a quarter of a century, he thought.

Therefore, if looked after they probably still have years of useful life left in them.

They have expected useful lives of about 40 years each.

I still have one or two but they are near the end of their useful life.

He said she could have expected three or four more years of useful life.

The current bridge is at the end of its useful life.

But those machines were just about at the end of their useful lives.

We can have good and useful lives, if people will help.

The system had at most another three years of useful life.

His hand was just now beginning to come back to useful life.