Meaning of いやみを必ず顔に表す


What does this line mean? いやみを必ず顔に表す

I know the individual words but I can't seem to figure out the meaning of the
sentence.




Probably, you recognise each of the words "[顔]{かお}" and "[表]{あらわ}す", don't
you?  
"顔に表す" is a phrase which means that someone shows his feelings on his face
obviously.

So, this sentence denotes, "The speaker never fails to show his sarcasm on his
face."

