插嘴 interrupt; chip in; put in a word; cut [chop; butt] in; interpose; break in; break in upon 插不上嘴 cannot get a word in edgeways; 在别人讲话时插嘴是不礼貌的。 it is not polite to interrupt when someone is talking
不用 1.(没有必要) need not 不用客气 don't mention it; don't stand on ceremony; 不用说 it goes without saying; needless to say; 不用着急。 you needn't worry.; there is no need to worry.2.(不使用) disuse; nonutility 这个词已经完全不用了。 the word has passed into complete disuse