blister

New hiking boots often cause a painful blister on the back of the heel.

(Chinese) 新的登山靴经常会在脚后跟上磨出一个疼的水疱。

The hot sun caused the paint on the old wooden door to swell and form a blister.

(Chinese) 烈日使旧木门上的油漆膨胀并形成了气泡。