English verb conjugation
OUGHT TO PREASCERTAIN

Regular verb: preascertain - preascertained - preascertained

Affirmation

Simple form	V-ing form
I ought to preascertain you ought to preascertain he ought to preascertain we ought to preascertain you ought to preascertain they ought to preascertain	I ought to be preascertaining you ought to be preascertaining he ought to be preascertaining we ought to be preascertaining you ought to be preascertaining they ought to be preascertaining
Perfect	V-ing perfect
I ought to have preascertained you ought to have preascertained he ought to have preascertained we ought to have preascertained you ought to have preascertained they ought to have preascertained	I ought to have been preascertaining you ought to have been preascertaining he ought to have been preascertaining we ought to have been preascertaining you ought to have been preascertaining they ought to have been preascertaining

Negation

Simple form	V-ing form
I oughtn't to preascertain you oughtn't to preascertain he oughtn't to preascertain we oughtn't to preascertain you oughtn't to preascertain they oughtn't to preascertain	I oughtn't to be preascertaining you oughtn't to be preascertaining he oughtn't to be preascertaining we oughtn't to be preascertaining you oughtn't to be preascertaining they oughtn't to be preascertaining
Perfect	V-ing perfect
I oughtn't to have preascertained you oughtn't to have preascertained he oughtn't to have preascertained we oughtn't to have preascertained you oughtn't to have preascertained they oughtn't to have preascertained	I oughtn't to have been preascertaining you oughtn't to have been preascertaining he oughtn't to have been preascertaining we oughtn't to have been preascertaining you oughtn't to have been preascertaining they oughtn't to have been preascertaining

Interrogative form

Simple form	V-ing form
ought to I preascertain? ought to you preascertain? ought to he preascertain? ought to we preascertain? ought to you preascertain? ought to they preascertain?	ought to I be preascertaining? ought to you be preascertaining? ought to he be preascertaining? ought to we be preascertaining? ought to you be preascertaining? ought to they be preascertaining?
Perfect	V-ing perfect
ought to I have preascertained? ought to you have preascertained? ought to he have preascertained? ought to we have preascertained? ought to you have preascertained? ought to they have preascertained?	ought to I have been preascertaining? ought to you have been preascertaining? ought to he have been preascertaining? ought to we have been preascertaining? ought to you have been preascertaining? ought to they have been preascertaining?

Interro-negative form

Simple form	V-ing form
oughtn't I to preascertain? oughtn't you to preascertain? oughtn't he to preascertain? oughtn't we to preascertain? oughtn't you to preascertain? oughtn't they to preascertain?	oughtn't I to be preascertaining? oughtn't you to be preascertaining? oughtn't he to be preascertaining? oughtn't we to be preascertaining? oughtn't you to be preascertaining? oughtn't they to be preascertaining?
Perfect	V-ing perfect
oughtn't I to have preascertained? oughtn't you to have preascertained? oughtn't he to have preascertained? oughtn't we to have preascertained? oughtn't you to have preascertained? oughtn't they to have preascertained?	oughtn't I to have been preascertaining? oughtn't you to have been preascertaining? oughtn't he to have been preascertaining? oughtn't we to have been preascertaining? oughtn't you to have been preascertaining? oughtn't they to have been preascertaining?