could research
Verbe régulier : research - researched- researched
Traduction française : faire des recherches sur - faire des recherches ou de la recherche 

Affirmation 	
Forme simple 	Forme en V-ing 	Perfect 	Perfect en V-ing 	
I could research
you could research
he could research
we could research
you could research
they could research 	I could be researching
you could be researching
he could be researching
we could be researching
you could be researching
they could be researching	I could have researched
you could have researched
he could have researched
we could have researched
you could have researched
they could have researched	I could have been researching
you could have been researching
he could have been researching
we could have been researching
you could have been researching
they could have been researching	

Négation 	
Forme simple 	Forme en V-ing 	Perfect 	Perfect en V-ing 	
I could not research
you could not research
he could not research
we could not research
you could not research
they could not research 	I could not be researching
you could not be researching
he could not be researching
we could not be researching
you could not be researching
they could not be researching	I could not have researched
you could not have researched
he could not have researched
we could not have researched
you could not have researched
they could not have researched	I could not have been researching
you could not have been researching
he could not have been researching
we could not have been researching
you could not have been researching
they could not have been researching	

Forme interrogative 	
Forme simple 	Forme en V-ing 	Perfect 	Perfect en V-ing 	
could I research?
could you research?
could he research?
could we research?
could you research?
could they research? 	could I be researching?
could you be researching?
could he be researching?
could we be researching?
could you be researching?
could they be researching? 	could I have researched?
could you have researched?
could he have researched?
could we have researched?
could you have researched?
could they have researched? 	could I have been researching?
could you have been researching?
could he have been researching?
could we have been researching?
could you have been researching?
could they have been researching? 	

Forme interro-négative 	
Forme simple 	Forme en V-ing 	Perfect 	Perfect en V-ing 	
could I not research?
could you not research?
could he not research?
could we not research?
could you not research?
could they not research? 	could I not be researching?
could you not be researching?
could he not be researching?
could we not be researching?
could you not be researching?
could they not be researching? 	could I not have researched?
could you not have researched?
could he not have researched?
could we not have researched?
could you not have researched?
could they not have researched? 	could I not have been researching?
could you not have been researching?
could he not have been researching?
could we not have been researching?
could you not have been researching?
could they not have been researching?