You [ would / should ] come home by six. あなたは6時までに家に戻るべきです。

They [ must / should ] finish their homework before going out to play.　外で遊ぶ前に宿題を終わらせなければなりません。

"[ Can / Will ] I use this computer?" "Sure!"

You look quite well; you [ cannot / must not ] be sick.

[ Shall / May ] I come in?

My sister is 3 years old. She [ can't / mustn't ] answer such a difficult question.

My brother is 16 years old. He [ can't / must ] answer such an easy question.

My sister's baby [ will be able to / will can ] walk soon.

You [ have not to/ don't have to ] wake up early tomorrow. It' s a holiday!

The ring [ can't / must ] be expensive. A real diamond is on it.

本物のダイヤモンドがついているんだから…？

Usopp always tells lies. That story [ can't / must ] be true.