must upspring
Irregular verb: upspring - upsprang, upsprung- upsprung

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
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	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I must not upspring
you must not upspring
he must not upspring
we must not upspring
you must not upspring
they must not upspring 	I must not be upspringing
you must not be upspringing
he must not be upspringing
we must not be upspringing
you must not be upspringing
they must not be upspringing	I must not have upsprung
you must not have upsprung
he must not have upsprung
we must not have upsprung
you must not have upsprung
they must not have upsprung	I must not have been upspringing
you must not have been upspringing
he must not have been upspringing
we must not have been upspringing
you must not have been upspringing
they must not have been upspringing	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
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? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
must I not upspring?
must you not upspring?
must he not upspring?
must we not upspring?
must you not upspring?
must they not upspring? 	must I not be upspringing?
must you not be upspringing?
must he not be upspringing?
must we not be upspringing?
must you not be upspringing?
must they not be upspringing? 	must I not have upsprung?
must you not have upsprung?
must he not have upsprung?
must we not have upsprung?
must you not have upsprung?
must they not have upsprung? 	must I not have been upspringing?
must you not have been upspringing?
must he not have been upspringing?
must we not have been upspringing?
must you not have been upspringing?
must they not have been upspringing?