“You should know better!”

In this crossword question, the answer is ‘TSK‘. The clue for this answer is “You should know better!“, which implies that the person is making a sound of disapproval, usually made by sucking air through the teeth. This sound of disapproval is often used when someone has made a mistake or done something wrong. The term ‘TSK‘ is commonly used to represent this sound in written form, and it is often used to express annoyance or disapproval at someone’s actions or behavior. Therefore, in this crossword question, the answer ‘TSK‘ is a representation of the disapproving sound made by someone who says “You should know better!“