I must separate you must separate she must separate we must separate you must separate they must separate
V-ing form
I must be separating you must be separating she must be separating we must be separating you must be separating they must be separating
Perfect
I must have separated you must have separated she must have separated we must have separated you must have separated they must have separated
V-ing perfect
I must have been separating you must have been separating she must have been separating we must have been separating you must have been separating they must have been separating
Negation
Simple form
I must not separate you must not separate she must not separate we must not separate you must not separate they must not separate
V-ing form
I must not be separating you must not be separating she must not be separating we must not be separating you must not be separating they must not be separating
Perfect
I must not have separated you must not have separated she must not have separated we must not have separated you must not have separated they must not have separated
V-ing perfect
I must not have been separating you must not have been separating she must not have been separating we must not have been separating you must not have been separating they must not have been separating
Interrogative form
Simple form
must I separate? must you separate? must she separate? must we separate? must you separate? must they separate?
V-ing form
must I be separating? must you be separating? must she be separating? must we be separating? must you be separating? must they be separating?
Perfect
must I have separated? must you have separated? must she have separated? must we have separated? must you have separated? must they have separated?
V-ing perfect
must I have been separating? must you have been separating? must she have been separating? must we have been separating? must you have been separating? must they have been separating?
Interro-negative form
Simple form
must I not separate? must you not separate? must she not separate? must we not separate? must you not separate? must they not separate?
V-ing form
must I not be separating? must you not be separating? must she not be separating? must we not be separating? must you not be separating? must they not be separating?
Perfect
must I not have separated? must you not have separated? must she not have separated? must we not have separated? must you not have separated? must they not have separated?
V-ing perfect
must I not have been separating? must you not have been separating? must she not have been separating? must we not have been separating? must you not have been separating? must they not have been separating?