I must stagnate you must stagnate she must stagnate we must stagnate you must stagnate they must stagnate
V-ing form
I must be stagnating you must be stagnating she must be stagnating we must be stagnating you must be stagnating they must be stagnating
Perfect
I must have stagnated you must have stagnated she must have stagnated we must have stagnated you must have stagnated they must have stagnated
V-ing perfect
I must have been stagnating you must have been stagnating she must have been stagnating we must have been stagnating you must have been stagnating they must have been stagnating
Negation
Simple form
I must not stagnate you must not stagnate she must not stagnate we must not stagnate you must not stagnate they must not stagnate
V-ing form
I must not be stagnating you must not be stagnating she must not be stagnating we must not be stagnating you must not be stagnating they must not be stagnating
Perfect
I must not have stagnated you must not have stagnated she must not have stagnated we must not have stagnated you must not have stagnated they must not have stagnated
V-ing perfect
I must not have been stagnating you must not have been stagnating she must not have been stagnating we must not have been stagnating you must not have been stagnating they must not have been stagnating
Interrogative form
Simple form
must I stagnate? must you stagnate? must she stagnate? must we stagnate? must you stagnate? must they stagnate?
V-ing form
must I be stagnating? must you be stagnating? must she be stagnating? must we be stagnating? must you be stagnating? must they be stagnating?
Perfect
must I have stagnated? must you have stagnated? must she have stagnated? must we have stagnated? must you have stagnated? must they have stagnated?
V-ing perfect
must I have been stagnating? must you have been stagnating? must she have been stagnating? must we have been stagnating? must you have been stagnating? must they have been stagnating?
Interro-negative form
Simple form
must I not stagnate? must you not stagnate? must she not stagnate? must we not stagnate? must you not stagnate? must they not stagnate?
V-ing form
must I not be stagnating? must you not be stagnating? must she not be stagnating? must we not be stagnating? must you not be stagnating? must they not be stagnating?
Perfect
must I not have stagnated? must you not have stagnated? must she not have stagnated? must we not have stagnated? must you not have stagnated? must they not have stagnated?
V-ing perfect
must I not have been stagnating? must you not have been stagnating? must she not have been stagnating? must we not have been stagnating? must you not have been stagnating? must they not have been stagnating?