go down on

US /ɡoʊ daʊn ɑn/
UK /ɡoʊ daʊn ɑn/
"go down on" picture
1.

口交

to perform oral sex on someone

:
He asked her to go down on him.
他让她给他口交
They decided to go down on each other.
他们决定互相口交