“Can't judge a book by its cover”
MEANING: An outward appearance cannot be an indicator of someone or something's value or worth
SENTENCE: You can’t judge a book by its cover as many university professors move around the university campus like students.
“Drastic times call for drastic measures”
MEANING: When undesirable circumstances are countered by drastic actions
SENTENCE: To curb the spread of the deadly epidemic virus, it was decided by the administration to build many quarantine centers at all borders as drastic times call for drastic measures.
“Costs an arm and a leg”
MEANING: To be extremely expensive.
SENTENCE: I would love to buy a beach view apartment but it costs an arm and a leg.