ought to flatten
Regular verb: flatten - flattened- flattened

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I ought to flatten
you ought to flatten
he ought to flatten
we ought to flatten
you ought to flatten
they ought to flatten 	I ought to be flattening
you ought to be flattening
he ought to be flattening
we ought to be flattening
you ought to be flattening
they ought to be flattening	I ought to have flattened
you ought to have flattened
he ought to have flattened
we ought to have flattened
you ought to have flattened
they ought to have flattened	I ought to have been flattening
you ought to have been flattening
he ought to have been flattening
we ought to have been flattening
you ought to have been flattening
they ought to have been flattening	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I oughtn't to flatten
you oughtn't to flatten
he oughtn't to flatten
we oughtn't to flatten
you oughtn't to flatten
they oughtn't to flatten 	I oughtn't to be flattening
you oughtn't to be flattening
he oughtn't to be flattening
we oughtn't to be flattening
you oughtn't to be flattening
they oughtn't to be flattening	I oughtn't to have flattened
you oughtn't to have flattened
he oughtn't to have flattened
we oughtn't to have flattened
you oughtn't to have flattened
they oughtn't to have flattened	I oughtn't to have been flattening
you oughtn't to have been flattening
he oughtn't to have been flattening
we oughtn't to have been flattening
you oughtn't to have been flattening
they oughtn't to have been flattening	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
ought to I flatten?
ought to you flatten?
ought to he flatten?
ought to we flatten?
ought to you flatten?
ought to they flatten? 	ought to I be flattening?
ought to you be flattening?
ought to he be flattening?
ought to we be flattening?
ought to you be flattening?
ought to they be flattening? 	ought to I have flattened?
ought to you have flattened?
ought to he have flattened?
ought to we have flattened?
ought to you have flattened?
ought to they have flattened? 	ought to I have been flattening?
ought to you have been flattening?
ought to he have been flattening?
ought to we have been flattening?
ought to you have been flattening?
ought to they have been flattening? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
oughtn't I to flatten?
oughtn't you to flatten?
oughtn't he to flatten?
oughtn't we to flatten?
oughtn't you to flatten?
oughtn't they to flatten? 	oughtn't I to be flattening?
oughtn't you to be flattening?
oughtn't he to be flattening?
oughtn't we to be flattening?
oughtn't you to be flattening?
oughtn't they to be flattening? 	oughtn't I to have flattened?
oughtn't you to have flattened?
oughtn't he to have flattened?
oughtn't we to have flattened?
oughtn't you to have flattened?
oughtn't they to have flattened? 	oughtn't I to have been flattening?
oughtn't you to have been flattening?
oughtn't he to have been flattening?
oughtn't we to have been flattening?
oughtn't you to have been flattening?
oughtn't they to have been flattening?