长途徒步后，我的脚跟上长了一个疼痛的水疱。

I got a painful ___blister on my heel after the long hike.

连续几天穿着过紧的鞋子，让我双脚都起了水泡。

Wearing tight shoes for days left ___blisters on both my feet.

炙热的阳光使窗框上的旧油漆起了泡。

The hot sun caused ___blisters to form in the old paint on the window frame.