These books fail to notice that the act has become dull.

This is for sad people, whose eyes have become dull.

But now life has become affluent and dull and there is a plenty of everything.

Murder itself has become routine and dull, so who wants to read about it?

My senses seemed suddenly to have become dull and unresponsive.

The execution, going on since early that morning, had become dull and routine.

The trip was beginning to consider becoming slightly dull.

He broke up the dinner by becoming dull, and saw his companion on her car.

The area of the park was becoming dull and needed an overhaul.

It was now red and had become quite dull.