Present
I ascertain
you ascertain
he ascertains
we ascertain
you ascertain
they ascertain

Perfect
I have ascertained
you have ascertained
he has ascertained
we have ascertained
you have ascertained
they have ascertained

Past
I ascertained
you ascertained
he ascertained
we ascertained
you ascertained
they ascertained

Pluperfect
I had ascertained
you had ascertained
he had ascertained
we had ascertained
you had ascertained
they had ascertained

Future
I will ascertain
you will ascertain
he will ascertain
we will ascertain
you will ascertain
they will ascertain

Future perfect
I will have ascertained
you will have ascertained
he will have ascertained
we will have ascertained
you will have ascertained
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Present
I ascertain
you ascertain
he ascertain
we ascertain
you ascertain
they ascertain

Present
I have ascertained
you have ascertained
he have ascertained
we have ascertained
you have ascertained
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Imperfect
I ascertained
you ascertained
he ascertained
we ascertained
you ascertained
they ascertained

Pluperfect
I had ascertained
you had ascertained
he had ascertained
we had ascertained
you had ascertained
they had ascertained

Present
I would ascertain
you would ascertain
he would ascertain
we would ascertain
you would ascertain
they would ascertain

Perfect
I would have ascertained
you would have ascertained
he would have ascertained
we would have ascertained
you would have ascertained
they would have ascertained

you ascertain
we Let's ascertain
you ascertain

Present
I am ascertaining
you are ascertaining
he is ascertaining
we are ascertaining
you are ascertaining
they are ascertaining

Perfect
I have been ascertaining
you have been ascertaining
he has been ascertaining
we have been ascertaining
you have been ascertaining
they have been ascertaining

Past
I was ascertaining
you were ascertaining
he was ascertaining
we were ascertaining
you were ascertaining
they were ascertaining

Pluperfect
I had been ascertaining
you had been ascertaining
he had been ascertaining
we had been ascertaining
you had been ascertaining
they had been ascertaining

Future
I will be ascertaining
you will be ascertaining
he will be ascertaining
we will be ascertaining
you will be ascertaining
they will be ascertaining

Future perfect
I will have been ascertaining
you will have been ascertaining
he will have been ascertaining
we will have been ascertaining
you will have been ascertaining
they will have been ascertaining

Present
I would be ascertaining
you would be ascertaining
he would be ascertaining
we would be ascertaining
you would be ascertaining
they would be ascertaining

Perfect
I would have been ascertaining
you would have been ascertaining
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we would have been ascertaining
you would have been ascertaining
they would have been ascertaining