should preascertain
Verbo regular: preascertain - preascertained- preascertained

Afirmación 	
Forma simple 	Forma con V-ing 	Perfecto 	Perfecto con V-ing 	
I should preascertain
you should preascertain
he should preascertain
we should preascertain
you should preascertain
they should preascertain 	I should be preascertaining
you should be preascertaining
he should be preascertaining
we should be preascertaining
you should be preascertaining
they should be preascertaining	I should have preascertained
you should have preascertained
he should have preascertained
we should have preascertained
you should have preascertained
they should have preascertained	I should have been preascertaining
you should have been preascertaining
he should have been preascertaining
we should have been preascertaining
you should have been preascertaining
they should have been preascertaining	

Negación 	
Forma simple 	Forma con V-ing 	Perfecto 	Perfecto con V-ing 	
I should not preascertain
you should not preascertain
he should not preascertain
we should not preascertain
you should not preascertain
they should not preascertain 	I should not be preascertaining
you should not be preascertaining
he should not be preascertaining
we should not be preascertaining
you should not be preascertaining
they should not be preascertaining	I should not have preascertained
you should not have preascertained
he should not have preascertained
we should not have preascertained
you should not have preascertained
they should not have preascertained	I should not have been preascertaining
you should not have been preascertaining
he should not have been preascertaining
we should not have been preascertaining
you should not have been preascertaining
they should not have been preascertaining	

Forma interrogativa 	
Forma simple 	Forma con V-ing 	Perfecto 	Perfecto con V-ing 	
should I preascertain?
should you preascertain?
should he preascertain?
should we preascertain?
should you preascertain?
should they preascertain? 	should I be preascertaining?
should you be preascertaining?
should he be preascertaining?
should we be preascertaining?
should you be preascertaining?
should they be preascertaining? 	should I have preascertained?
should you have preascertained?
should he have preascertained?
should we have preascertained?
should you have preascertained?
should they have preascertained? 	should I have been preascertaining?
should you have been preascertaining?
should he have been preascertaining?
should we have been preascertaining?
should you have been preascertaining?
should they have been preascertaining? 	

Forma interro-negativa 	
Forma simple 	Forma con V-ing 	Perfecto 	Perfecto con V-ing 	
should I not preascertain?
should you not preascertain?
should he not preascertain?
should we not preascertain?
should you not preascertain?
should they not preascertain? 	should I not be preascertaining?
should you not be preascertaining?
should he not be preascertaining?
should we not be preascertaining?
should you not be preascertaining?
should they not be preascertaining? 	should I not have preascertained?
should you not have preascertained?
should he not have preascertained?
should we not have preascertained?
should you not have preascertained?
should they not have preascertained? 	should I not have been preascertaining?
should you not have been preascertaining?
should he not have been preascertaining?
should we not have been preascertaining?
should you not have been preascertaining?
should they not have been preascertaining?