Seeing someone dead made the training take on a more serious tone.

The next seven missions took on a very serious tone.

She looked round at him, surprised by his serious tone.

Then in a serious tone of voice he asked: "Where do we go from here?"

She looked up again, pleased by the serious tone of his question.

But she also continued in the same serious tone of voice.

His voice now had a different tone, serious and respectful.

The music actually has a surprisingly serious tone to it.

The French take a less serious tone and call it teddy.

"We had to get you out," he told her in a more serious tone.