present
I ascertain
You ascertain
He ascertains
She ascertains
It ascertains
We ascertain
They ascertain
past
I ascertained
You ascertained
He ascertained
She ascertained
It ascertained
We ascertained
They ascertained
future
I will ascertain
You will ascertain
He will ascertain
She will ascertain
It will ascertain
We will ascertain
They will ascertain
conditional
I would ascertain
You would ascertain
He would ascertain
She would ascertain
It would ascertain
We would ascertain
They would ascertain