can preascertain
Verbe régulier : preascertain - preascertained- preascertained

Affirmation 	
Forme simple 	Forme en V-ing 	Perfect 	Perfect en V-ing 	
I can preascertain
you can preascertain
she can preascertain
we can preascertain
you can preascertain
they can preascertain 	I can be preascertaining
you can be preascertaining
she can be preascertaining
we can be preascertaining
you can be preascertaining
they can be preascertaining	I can have preascertained
you can have preascertained
she can have preascertained
we can have preascertained
you can have preascertained
they can have preascertained	I can have been preascertaining
you can have been preascertaining
she can have been preascertaining
we can have been preascertaining
you can have been preascertaining
they can have been preascertaining	

Négation 	
Forme simple 	Forme en V-ing 	Perfect 	Perfect en V-ing 	
I cannot preascertain
you cannot preascertain
she cannot preascertain
we cannot preascertain
you cannot preascertain
they cannot preascertain 	I cannot be preascertaining
you cannot be preascertaining
she cannot be preascertaining
we cannot be preascertaining
you cannot be preascertaining
they cannot be preascertaining	I cannot have preascertained
you cannot have preascertained
she cannot have preascertained
we cannot have preascertained
you cannot have preascertained
they cannot have preascertained	I cannot have been preascertaining
you cannot have been preascertaining
she cannot have been preascertaining
we cannot have been preascertaining
you cannot have been preascertaining
they cannot have been preascertaining	

Forme interrogative 	
Forme simple 	Forme en V-ing 	Perfect 	Perfect en V-ing 	
can I preascertain?
can you preascertain?
can she preascertain?
can we preascertain?
can you preascertain?
can they preascertain? 	can I be preascertaining?
can you be preascertaining?
can she be preascertaining?
can we be preascertaining?
can you be preascertaining?
can they be preascertaining? 	can I have preascertained?
can you have preascertained?
can she have preascertained?
can we have preascertained?
can you have preascertained?
can they have preascertained? 	can I have been preascertaining?
can you have been preascertaining?
can she have been preascertaining?
can we have been preascertaining?
can you have been preascertaining?
can they have been preascertaining? 	

Forme interro-négative 	
Forme simple 	Forme en V-ing 	Perfect 	Perfect en V-ing 	
can I not preascertain?
can you not preascertain?
can she not preascertain?
can we not preascertain?
can you not preascertain?
can they not preascertain? 	can I not be preascertaining?
can you not be preascertaining?
can she not be preascertaining?
can we not be preascertaining?
can you not be preascertaining?
can they not be preascertaining? 	can I not have preascertained?
can you not have preascertained?
can she not have preascertained?
can we not have preascertained?
can you not have preascertained?
can they not have preascertained? 	can I not have been preascertaining?
can you not have been preascertaining?
can she not have been preascertaining?
can we not have been preascertaining?
can you not have been preascertaining?
can they not have been preascertaining?