I must marvel you must marvel she must marvel we must marvel you must marvel they must marvel
V-ing form
I must be marvelling you must be marvelling she must be marvelling we must be marvelling you must be marvelling they must be marvelling
Perfect
I must have marvelled you must have marvelled she must have marvelled we must have marvelled you must have marvelled they must have marvelled
V-ing perfect
I must have been marvelling you must have been marvelling she must have been marvelling we must have been marvelling you must have been marvelling they must have been marvelling
Negation
Simple form
I mustn't marvel you mustn't marvel she mustn't marvel we mustn't marvel you mustn't marvel they mustn't marvel
V-ing form
I mustn't be marvelling you mustn't be marvelling she mustn't be marvelling we mustn't be marvelling you mustn't be marvelling they mustn't be marvelling
Perfect
I mustn't have marvelled you mustn't have marvelled she mustn't have marvelled we mustn't have marvelled you mustn't have marvelled they mustn't have marvelled
V-ing perfect
I mustn't have been marvelling you mustn't have been marvelling she mustn't have been marvelling we mustn't have been marvelling you mustn't have been marvelling they mustn't have been marvelling
Interrogative form
Simple form
must I marvel? must you marvel? must she marvel? must we marvel? must you marvel? must they marvel?
V-ing form
must I be marvelling? must you be marvelling? must she be marvelling? must we be marvelling? must you be marvelling? must they be marvelling?
Perfect
must I have marvelled? must you have marvelled? must she have marvelled? must we have marvelled? must you have marvelled? must they have marvelled?
V-ing perfect
must I have been marvelling? must you have been marvelling? must she have been marvelling? must we have been marvelling? must you have been marvelling? must they have been marvelling?
Interro-negative form
Simple form
mustn't I marvel? mustn't you marvel? mustn't she marvel? mustn't we marvel? mustn't you marvel? mustn't they marvel?
V-ing form
mustn't I be marvelling? mustn't you be marvelling? mustn't she be marvelling? mustn't we be marvelling? mustn't you be marvelling? mustn't they be marvelling?
Perfect
mustn't I have marvelled? mustn't you have marvelled? mustn't she have marvelled? mustn't we have marvelled? mustn't you have marvelled? mustn't they have marvelled?
V-ing perfect
mustn't I have been marvelling? mustn't you have been marvelling? mustn't she have been marvelling? mustn't we have been marvelling? mustn't you have been marvelling? mustn't they have been marvelling?