1.   His voice cracked slightly as he tried to explain.

2.   My voice almost cracked as I made a little speech thanking them.

3.   She said his name, and her voice cracked.

4.   The voice cracked around her like a bullwhip.

5.   Her voice cracked and she began to cry.

6.   The voice cracked like a whip now, and the woman jumped.

7.   His voice cracked like a whip.

8.   Her voice cracked and she cleared her throat.

9.   Although his voice cracked frequently, Keene kept up his familiar rapid-fire conversational pace.

10.   And they can trade stocks at feasible commissions and without having to call a broker with the worry that their voice might crack.