Must
Ought to
Synonyms Ought to, have to, need to, be required to, be under an obligation to, should, have got to, be obliged to, and be compelled to.
Not to be missed
Synonyms Not to be missed, necessity, necessary thing, requirement, very good, essential, sine qua non, and requisite.
Mould
Synonyms Mould, mouldiness, fustiness, mustiness, mildew, and decay.
Example Sentences
You must complete your homework today.
We must respect each other's opinions.
She must attend the meeting tomorrow.
They must follow the safety guidelines.