だめですよ

must; must not

→ 駄目だ
phrase Rare #29,701
must; must not Used to give advice or state a rule. After a negative form such as しなければ or ないと, it means “must.” After ては, it means “must not.” Used alone, it can mean “you can't” or “not now.”
JA: ここで写真を撮ってはだめですよ。
EN: You must not take pictures here.

飲まなきゃだめですよ鼻血失った血を補給するため

You have to drink it to replenish the blood you lost from the nosebleed.

— サスペリア (1977)

悪いことしてだめですよ

You mustn't do bad things.

今はだめですよ

Not right now.

— ウィキッド ふたりの魔女 (2024)

もっと自分を大切にしなければだめですよ

You need to take better care of yourself.

だめですよ

No, you can't.

— Бриллиантовая рука (1969)

強く大きくなるためにちゃんとご飯食べないとだめですよ

You need to eat properly if you want to grow up big and strong.