could ascertain
Verbo regolare: ascertain - ascertained- ascertained

Affermazione 	
Forma semplice 	Forma con V-ing 	Perfetto 	Perfetto con V-ing 	
I could ascertain
you could ascertain
she could ascertain
we could ascertain
you could ascertain
they could ascertain 	I could be ascertaining
you could be ascertaining
she could be ascertaining
we could be ascertaining
you could be ascertaining
they could be ascertaining	I could have ascertained
you could have ascertained
she could have ascertained
we could have ascertained
you could have ascertained
they could have ascertained	I could have been ascertaining
you could have been ascertaining
she could have been ascertaining
we could have been ascertaining
you could have been ascertaining
they could have been ascertaining	

Negazione 	
Forma semplice 	Forma con V-ing 	Perfetto 	Perfetto con V-ing 	
I could not ascertain
you could not ascertain
she could not ascertain
we could not ascertain
you could not ascertain
they could not ascertain 	I could not be ascertaining
you could not be ascertaining
she could not be ascertaining
we could not be ascertaining
you could not be ascertaining
they could not be ascertaining	I could not have ascertained
you could not have ascertained
she could not have ascertained
we could not have ascertained
you could not have ascertained
they could not have ascertained	I could not have been ascertaining
you could not have been ascertaining
she could not have been ascertaining
we could not have been ascertaining
you could not have been ascertaining
they could not have been ascertaining	

Forma interrogativa 	
Forma semplice 	Forma con V-ing 	Perfetto 	Perfetto con V-ing 	
could I ascertain?
could you ascertain?
could she ascertain?
could we ascertain?
could you ascertain?
could they ascertain? 	could I be ascertaining?
could you be ascertaining?
could she be ascertaining?
could we be ascertaining?
could you be ascertaining?
could they be ascertaining? 	could I have ascertained?
could you have ascertained?
could she have ascertained?
could we have ascertained?
could you have ascertained?
could they have ascertained? 	could I have been ascertaining?
could you have been ascertaining?
could she have been ascertaining?
could we have been ascertaining?
could you have been ascertaining?
could they have been ascertaining? 	

Forma interro-negativa 	
Forma semplice 	Forma con V-ing 	Perfetto 	Perfetto con V-ing 	
could I not ascertain?
could you not ascertain?
could she not ascertain?
could we not ascertain?
could you not ascertain?
could they not ascertain? 	could I not be ascertaining?
could you not be ascertaining?
could she not be ascertaining?
could we not be ascertaining?
could you not be ascertaining?
could they not be ascertaining? 	could I not have ascertained?
could you not have ascertained?
could she not have ascertained?
could we not have ascertained?
could you not have ascertained?
could they not have ascertained? 	could I not have been ascertaining?
could you not have been ascertaining?
could she not have been ascertaining?
could we not have been ascertaining?
could you not have been ascertaining?
could they not have been ascertaining?