must stub
Regular verb: stub - stubbed- stubbed

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I must stub
you must stub
he must stub
we must stub
you must stub
they must stub 	I must be stubbing
you must be stubbing
he must be stubbing
we must be stubbing
you must be stubbing
they must be stubbing	I must have stubbed
you must have stubbed
he must have stubbed
we must have stubbed
you must have stubbed
they must have stubbed	I must have been stubbing
you must have been stubbing
he must have been stubbing
we must have been stubbing
you must have been stubbing
they must have been stubbing	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I must not stub
you must not stub
he must not stub
we must not stub
you must not stub
they must not stub 	I must not be stubbing
you must not be stubbing
he must not be stubbing
we must not be stubbing
you must not be stubbing
they must not be stubbing	I must not have stubbed
you must not have stubbed
he must not have stubbed
we must not have stubbed
you must not have stubbed
they must not have stubbed	I must not have been stubbing
you must not have been stubbing
he must not have been stubbing
we must not have been stubbing
you must not have been stubbing
they must not have been stubbing	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
must I stub?
must you stub?
must he stub?
must we stub?
must you stub?
must they stub? 	must I be stubbing?
must you be stubbing?
must he be stubbing?
must we be stubbing?
must you be stubbing?
must they be stubbing? 	must I have stubbed?
must you have stubbed?
must he have stubbed?
must we have stubbed?
must you have stubbed?
must they have stubbed? 	must I have been stubbing?
must you have been stubbing?
must he have been stubbing?
must we have been stubbing?
must you have been stubbing?
must they have been stubbing? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
must I not stub?
must you not stub?
must he not stub?
must we not stub?
must you not stub?
must they not stub? 	must I not be stubbing?
must you not be stubbing?
must he not be stubbing?
must we not be stubbing?
must you not be stubbing?
must they not be stubbing? 	must I not have stubbed?
must you not have stubbed?
must he not have stubbed?
must we not have stubbed?
must you not have stubbed?
must they not have stubbed? 	must I not have been stubbing?
must you not have been stubbing?
must he not have been stubbing?
must we not have been stubbing?
must you not have been stubbing?
must they not have been stubbing?