English verb conjugation MUST ASCERTAIN

Regular verb: ascertain - ascertained - ascertained

Affirmation

Simple form

I must ascertain
you must ascertain
he must ascertain
we must ascertain
you must ascertain
they must ascertain

V-ing form

I must be ascertaining
you must be ascertaining
he must be ascertaining
we must be ascertaining
you must be ascertaining
they must be ascertaining

Perfect

I must have ascertained
you must have ascertained
he must have ascertained
we must have ascertained
you must have ascertained
they must have ascertained

V-ing perfect

I must have been ascertaining
you must have been ascertaining
he must have been ascertaining
we must have been ascertaining
you must have been ascertaining
they must have been ascertaining

Negation

Simple form

I mustn't ascertain
you mustn't ascertain
he mustn't ascertain
we mustn't ascertain
you mustn't ascertain
they mustn't ascertain

V-ing form

I mustn't be ascertaining
you mustn't be ascertaining
he mustn't be ascertaining
we mustn't be ascertaining
you mustn't be ascertaining
they mustn't be ascertaining

Perfect

I mustn't have ascertained
you mustn't have ascertained
he mustn't have ascertained
we mustn't have ascertained
you mustn't have ascertained
they mustn't have ascertained

V-ing perfect

I mustn't have been ascertaining
you mustn't have been ascertaining
he mustn't have been ascertaining
we mustn't have been ascertaining
you mustn't have been ascertaining
they mustn't have been ascertaining

Interrogative form

Simple form

must I ascertain?
must you ascertain?
must he ascertain?
must we ascertain?
must you ascertain?
must they ascertain?

V-ing form

must I be ascertaining?
must you be ascertaining?
must he be ascertaining?
must we be ascertaining?
must you be ascertaining?
must they be ascertaining?

Perfect

must I have ascertained?
must you have ascertained?
must he have ascertained?
must we have ascertained?
must you have ascertained?
must they have ascertained?

V-ing perfect

must I have been ascertaining?
must you have been ascertaining?
must he have been ascertaining?
must we have been ascertaining?
must you have been ascertaining?
must they have been ascertaining?

Interro-negative form

Simple form

mustn't I ascertain?
mustn't you ascertain?
mustn't he ascertain?
mustn't we ascertain?
mustn't you ascertain?
mustn't they ascertain?

V-ing form

mustn't I be ascertaining?
mustn't you be ascertaining?
mustn't he be ascertaining?
mustn't we be ascertaining?
mustn't you be ascertaining?
mustn't they be ascertaining?

Perfect

mustn't I have ascertained?
mustn't you have ascertained?
mustn't he have ascertained?
mustn't we have ascertained?
mustn't you have ascertained?
mustn't they have ascertained?

V-ing perfect

mustn't I have been ascertaining?
mustn't you have been ascertaining?
mustn't he have been ascertaining?
mustn't we have been ascertaining?
mustn't you have been ascertaining?
mustn't they have been ascertaining?

Page top