must upspring
Verbe irrégulier : upspring - upsprang, upsprung- upsprung

Affirmation 	
Forme simple 	Forme en V-ing 	Perfect 	Perfect en V-ing 	
I must upspring
you must upspring
he must upspring
we must upspring
you must upspring
they must upspring 	I must be upspringing
you must be upspringing
he must be upspringing
we must be upspringing
you must be upspringing
they must be upspringing	I must have upsprung
you must have upsprung
he must have upsprung
we must have upsprung
you must have upsprung
they must have upsprung	I must have been upspringing
you must have been upspringing
he must have been upspringing
we must have been upspringing
you must have been upspringing
they must have been upspringing	

Négation 	
Forme simple 	Forme en V-ing 	Perfect 	Perfect en V-ing 	
I mustn't upspring
you mustn't upspring
he mustn't upspring
we mustn't upspring
you mustn't upspring
they mustn't upspring 	I mustn't be upspringing
you mustn't be upspringing
he mustn't be upspringing
we mustn't be upspringing
you mustn't be upspringing
they mustn't be upspringing	I mustn't have upsprung
you mustn't have upsprung
he mustn't have upsprung
we mustn't have upsprung
you mustn't have upsprung
they mustn't have upsprung	I mustn't have been upspringing
you mustn't have been upspringing
he mustn't have been upspringing
we mustn't have been upspringing
you mustn't have been upspringing
they mustn't have been upspringing	

Forme interrogative 	
Forme simple 	Forme en V-ing 	Perfect 	Perfect en V-ing 	
must I upspring?
must you upspring?
must he upspring?
must we upspring?
must you upspring?
must they upspring? 	must I be upspringing?
must you be upspringing?
must he be upspringing?
must we be upspringing?
must you be upspringing?
must they be upspringing? 	must I have upsprung?
must you have upsprung?
must he have upsprung?
must we have upsprung?
must you have upsprung?
must they have upsprung? 	must I have been upspringing?
must you have been upspringing?
must he have been upspringing?
must we have been upspringing?
must you have been upspringing?
must they have been upspringing? 	

Forme interro-négative 	
Forme simple 	Forme en V-ing 	Perfect 	Perfect en V-ing 	
mustn't I upspring?
mustn't you upspring?
mustn't he upspring?
mustn't we upspring?
mustn't you upspring?
mustn't they upspring? 	mustn't I be upspringing?
mustn't you be upspringing?
mustn't he be upspringing?
mustn't we be upspringing?
mustn't you be upspringing?
mustn't they be upspringing? 	mustn't I have upsprung?
mustn't you have upsprung?
mustn't he have upsprung?
mustn't we have upsprung?
mustn't you have upsprung?
mustn't they have upsprung? 	mustn't I have been upspringing?
mustn't you have been upspringing?
mustn't he have been upspringing?
mustn't we have been upspringing?
mustn't you have been upspringing?
mustn't they have been upspringing?