1.   Skin thickens, dries and coarsens after sun exposure.

2.   But Ms. Hill said that such accounts had not prevented her from speaking out about sexual harassment and that her skin has thickened.

3.   Eventually his skin thickened.

4.   Friday, during his radio program, the host John Gambling asked him if his skin was thickening as time passes.

5.   In old people, immune systems might be strengthened, and skin thickened.

6.   Research shows that after extensive use, it can cause the skin to thicken.

7.   The back edge of these shoes can rub excessively against the heel, causing skin to thicken, which leads to calluses.

8.   The skin thickens.