1.   Her scrunched up face made her look as if she was wearing a perpetual mirthless grin.

2.   Walker seems to have a perpetual grin on his face.

3.   He seems to have a perpetual grin on his face.

4.   For the effervescent Maruyama, a perpetual grin is part of the daily grind.

5.   His blackened teeth are showcased in a perpetual grin.

6.   In interviews, Grant jokes, exaggerates and embellishes stories with a dry humor and an almost perpetual grin that he struggles vainly to suppress.

7.   It seems to wear a perpetual grin.

8.   Significantly for humans, the mouths of many species turn upward in a perpetual grin.

9.   With his grasshopper eyes bulging and his mouth cranked open in a perpetual demonic grin, you quickly realize that Milton is no mere mortal.