F'lar heard himself saying; felt his lips stretch into a smile he was far from feeling.

The full, very red lips stretched back to reveal large yellow teeth.

One simply blew out, then stretched wide the lips and chest.

Warm breath brushed my skin, and I felt his lips stretch into a grin.

He blinked, but then his lips stretched wide in a grin.

At his look of surprise, her faded lips stretched faintly, not quite a smile.

Reid's lips had stretched into a grin without his knowing it.

He gave a little shrug and his lips stretched to a thin smile.

I felt my lips stretch in a large, unconvincing grin.

Even Sisko felt his lips stretch into a smile at that image.