美 [pɪn daʊn] 英 [pɪn daʊn]
pin down
Verbdefine clearly;
"I cannot narrow down the rules for this game"
place in a confining or embarrassing position;
"He was trapped in a difficult situation"
attach with or as if with a pin;
"pin up a picture"
pin down近义词
peg down narrow down nail down specify narrow pin up trap
