dumb

adj.

1. 哑的
   • She is very kind to the dumb children.
     她对哑童非常好。
2. 说不出话的
   • He is dumb on the subject.
     他对这个问题表示沉默。
3. 愚蠢的
   • It was dumb of you to say that.
     你说这种话太愚蠢了。