strip (down) to something
phrasal verb with strip verb uk/strɪp/ us/strɪp/ -pp-
脱得只剩下…;把衣服脱到（身体某部位）
to remove everything except for a particular piece of clothing or above a particular part of the body
I had to strip down to my underwear for my medical examination. 体检时我得把衣服脱掉，只剩内衣。
He was stripped to the waist. 他被脱光了上衣。