must

mustとは　意味・定義・例文

Helping verb 助動詞

1. have to

～しなければならない

I must go home now.

2. be forced or required to do

～しなければいけない

You must not play catch on the street. ー Don't play catch on the street.

3. be sure to

～するはずである

She must have arrived at the office by now. ー She must be at the office by now.