根据句意，用所给动词的适当形式填空。
It’s getting dark. You’d better ____________ (not go) out now.
Sally took a photo of her friends while they ____________ (play) computer games.
Mary, ____________ (not reply) to your pen friend in the USA since you are too busy
Oil ____________ (catch) fire easily. You must be very careful.
At last, the two thieves ____________ (control) by the police.