I ought to ventilate you ought to ventilate she ought to ventilate we ought to ventilate you ought to ventilate they ought to ventilate
V-ing form
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
Perfect
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
V-ing perfect
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
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
V-ing form
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
Perfect
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
V-ing perfect
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
ought to I ventilate? ought to you ventilate? ought to she ventilate? ought to we ventilate? ought to you ventilate? ought to they ventilate?
V-ing form
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?
Perfect
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?
V-ing perfect
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
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?
V-ing form
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?
Perfect
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?
V-ing perfect
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?