ought to ventilate
Regular verb: ventilate - ventilated- ventilated

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I ought to ventilate
you ought to ventilate
she ought to ventilate
we ought to ventilate
you ought to ventilate
they ought to ventilate 	I ought to be ventilating
you ought to be ventilating
she ought to be ventilating
we ought to be ventilating
you ought to be ventilating
they ought to be ventilating	I ought to have ventilated
you ought to have ventilated
she ought to have ventilated
we ought to have ventilated
you ought to have ventilated
they ought to have ventilated	I ought to have been ventilating
you ought to have been ventilating
she ought to have been ventilating
we ought to have been ventilating
you ought to have been ventilating
they ought to have been ventilating	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I oughtn't to ventilate
you oughtn't to ventilate
she oughtn't to ventilate
we oughtn't to ventilate
you oughtn't to ventilate
they oughtn't to ventilate 	I oughtn't to be ventilating
you oughtn't to be ventilating
she oughtn't to be ventilating
we oughtn't to be ventilating
you oughtn't to be ventilating
they oughtn't to be ventilating	I oughtn't to have ventilated
you oughtn't to have ventilated
she oughtn't to have ventilated
we oughtn't to have ventilated
you oughtn't to have ventilated
they oughtn't to have ventilated	I oughtn't to have been ventilating
you oughtn't to have been ventilating
she oughtn't to have been ventilating
we oughtn't to have been ventilating
you oughtn't to have been ventilating
they oughtn't to have been ventilating	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
ought to I ventilate?
ought to you ventilate?
ought to she ventilate?
ought to we ventilate?
ought to you ventilate?
ought to they ventilate? 	ought to I be ventilating?
ought to you be ventilating?
ought to she be ventilating?
ought to we be ventilating?
ought to you be ventilating?
ought to they be ventilating? 	ought to I have ventilated?
ought to you have ventilated?
ought to she have ventilated?
ought to we have ventilated?
ought to you have ventilated?
ought to they have ventilated? 	ought to I have been ventilating?
ought to you have been ventilating?
ought to she have been ventilating?
ought to we have been ventilating?
ought to you have been ventilating?
ought to they have been ventilating? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
oughtn't I to ventilate?
oughtn't you to ventilate?
oughtn't she to ventilate?
oughtn't we to ventilate?
oughtn't you to ventilate?
oughtn't they to ventilate? 	oughtn't I to be ventilating?
oughtn't you to be ventilating?
oughtn't she to be ventilating?
oughtn't we to be ventilating?
oughtn't you to be ventilating?
oughtn't they to be ventilating? 	oughtn't I to have ventilated?
oughtn't you to have ventilated?
oughtn't she to have ventilated?
oughtn't we to have ventilated?
oughtn't you to have ventilated?
oughtn't they to have ventilated? 	oughtn't I to have been ventilating?
oughtn't you to have been ventilating?
oughtn't she to have been ventilating?
oughtn't we to have been ventilating?
oughtn't you to have been ventilating?
oughtn't they to have been ventilating?