“变钝”的拼音为：biàn dùn...

他使刀口卷刃[变钝].He turned the edge of the knife.这把便宜的刀容易变钝.This cheap knife dulls easily.刀变钝了.The knife's edge has turned....

“变钝”的英语可以翻译为：ust，obtund，failure ...