Cat got your tongue?
→  꿀먹은 벙어리야?

[예문]
A:Honey,where is this month's paychek?
  여보,이번달월금 어디있어요?

B:Well, uh....
   그게 글쎄...

A:What's the matter? Cat got your tongue?
  왜 그래요? 갑자기 꿀먹은 벙어리가 됐어요?

B:I am really sorry. Honey, I swear it won't happen again.
  정말 미안해,다시는 안그럴께.

*pay check :월급,급여.