1.   His voice thickened as he spoke, his eyes shone.

2.   Her voice had thickened by the time she managed to reply.

3.   Her voice was thickening, and so was her breathing.

4.   Her voice has thickened like molasses, but she still belts it out with a crisp, defined edge.

5.   Her voice thickens and tears form under her glasses as she reads from the photocopy she made when she donated the original letter to the museum.