English verb conjugation
COULD RESEARCH

Regular verb: research - researched - researched

Affirmation

Simple form	V-ing form
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
Perfect	V-ing perfect
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

Negation

Simple form	V-ing form
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
Perfect	V-ing perfect
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

Interrogative form

Simple form	V-ing form
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?
Perfect	V-ing perfect
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?

Interro-negative form

Simple form	V-ing form
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?
Perfect	V-ing perfect
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?