ought to stem
Regular verb: stem - stemmed- stemmed

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I ought to stem
you ought to stem
she ought to stem
we ought to stem
you ought to stem
they ought to stem 	I ought to be stemming
you ought to be stemming
she ought to be stemming
we ought to be stemming
you ought to be stemming
they ought to be stemming	I ought to have stemmed
you ought to have stemmed
she ought to have stemmed
we ought to have stemmed
you ought to have stemmed
they ought to have stemmed	I ought to have been stemming
you ought to have been stemming
she ought to have been stemming
we ought to have been stemming
you ought to have been stemming
they ought to have been stemming	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I oughtn't to stem
you oughtn't to stem
she oughtn't to stem
we oughtn't to stem
you oughtn't to stem
they oughtn't to stem 	I oughtn't to be stemming
you oughtn't to be stemming
she oughtn't to be stemming
we oughtn't to be stemming
you oughtn't to be stemming
they oughtn't to be stemming	I oughtn't to have stemmed
you oughtn't to have stemmed
she oughtn't to have stemmed
we oughtn't to have stemmed
you oughtn't to have stemmed
they oughtn't to have stemmed	I oughtn't to have been stemming
you oughtn't to have been stemming
she oughtn't to have been stemming
we oughtn't to have been stemming
you oughtn't to have been stemming
they oughtn't to have been stemming	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
ought to I stem?
ought to you stem?
ought to she stem?
ought to we stem?
ought to you stem?
ought to they stem? 	ought to I be stemming?
ought to you be stemming?
ought to she be stemming?
ought to we be stemming?
ought to you be stemming?
ought to they be stemming? 	ought to I have stemmed?
ought to you have stemmed?
ought to she have stemmed?
ought to we have stemmed?
ought to you have stemmed?
ought to they have stemmed? 	ought to I have been stemming?
ought to you have been stemming?
ought to she have been stemming?
ought to we have been stemming?
ought to you have been stemming?
ought to they have been stemming? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
oughtn't I to stem?
oughtn't you to stem?
oughtn't she to stem?
oughtn't we to stem?
oughtn't you to stem?
oughtn't they to stem? 	oughtn't I to be stemming?
oughtn't you to be stemming?
oughtn't she to be stemming?
oughtn't we to be stemming?
oughtn't you to be stemming?
oughtn't they to be stemming? 	oughtn't I to have stemmed?
oughtn't you to have stemmed?
oughtn't she to have stemmed?
oughtn't we to have stemmed?
oughtn't you to have stemmed?
oughtn't they to have stemmed? 	oughtn't I to have been stemming?
oughtn't you to have been stemming?
oughtn't she to have been stemming?
oughtn't we to have been stemming?
oughtn't you to have been stemming?
oughtn't they to have been stemming?