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 can't preascertain
you can't preascertain
she can't preascertain
we can't preascertain
you can't preascertain
they can't preascertain 	I can't be preascertaining
you can't be preascertaining
she can't be preascertaining
we can't be preascertaining
you can't be preascertaining
they can't be preascertaining	I can't have preascertained
you can't have preascertained
she can't have preascertained
we can't have preascertained
you can't have preascertained
they can't have preascertained	I can't have been preascertaining
you can't have been preascertaining
she can't have been preascertaining
we can't have been preascertaining
you can't have been preascertaining
they can't 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't I preascertain?
can't you preascertain?
can't she preascertain?
can't we preascertain?
can't you preascertain?
can't they preascertain? 	can't I be preascertaining?
can't you be preascertaining?
can't she be preascertaining?
can't we be preascertaining?
can't you be preascertaining?
can't they be preascertaining? 	can't I have preascertained?
can't you have preascertained?
can't she have preascertained?
can't we have preascertained?
can't you have preascertained?
can't they have preascertained? 	can't I have been preascertaining?
can't you have been preascertaining?
can't she have been preascertaining?
can't we have been preascertaining?
can't you have been preascertaining?
can't they have been preascertaining?