The service has a difficult balance to achieve,' she said.

Who plays this music, and how, determines the way a difficult balance among sources is reached.

You've got to maintain a rather difficult balance here, son.

It is a difficult balance to achieve, and the higher up the organization one goes, the more impossible the task seems.

The playwright is trying to achieve a difficult balance here.

"It's a difficult balance to present it as a guide and also say, 'Watch me,"' she said.

"This is a difficult balance because some of our producers get carried away."

The messy reality will probably result in some difficult balance among the groups competing for power.

It is a difficult balance to strike, and one which I believe should be given careful attention.

This is the difficult balance that we have to strike sometimes.