You must come and have tea with us.
ぜひうちへお茶にいらっしゃい
You must get up at 5 a.m. so as to catch the first train.
一番列車に間に合うように午前５時に起きなくてはいけません
You must have finished your report by next March.
君は来年の３月までにレポートを仕上げなければならない．
You must keep your credit cards safe.
クレジットカードは安全に保管しなさい
You must know yourself.
人はおのれ自身を知らねばならない
You must look to your health.
健康に注意しなければならない
You must needs [needs must] do your duty.
義務をはたさねばならぬ
You must not guess at the answers.
当て推量で答えてはいけない
You must not misbehave so.
そんな無作法をしてはいけない
You must so instruct them that they will not repeat the mistake.
過ちを繰り返さないよう指導しなくてはなりません
