English verb conjugation
COULD STUDY

Regular verb: study - studied - studied

Affirmation

Simple form	V-ing form
I could study you could study she could study we could study you could study they could study	I could be studying you could be studying she could be studying we could be studying you could be studying they could be studying
Perfect	V-ing perfect
I could have studied you could have studied she could have studied we could have studied you could have studied they could have studied	I could have been studying you could have been studying she could have been studying we could have been studying you could have been studying they could have been studying

Negation

Simple form	V-ing form
I could not study you could not study she could not study we could not study you could not study they could not study	I could not be studying you could not be studying she could not be studying we could not be studying you could not be studying they could not be studying
Perfect	V-ing perfect
I could not have studied you could not have studied she could not have studied we could not have studied you could not have studied they could not have studied	I could not have been studying you could not have been studying she could not have been studying we could not have been studying you could not have been studying they could not have been studying

Interrogative form

Simple form	V-ing form
could I study? could you study? could she study? could we study? could you study? could they study?	could I be studying? could you be studying? could she be studying? could we be studying? could you be studying? could they be studying?
Perfect	V-ing perfect
could I have studied? could you have studied? could she have studied? could we have studied? could you have studied? could they have studied?	could I have been studying? could you have been studying? could she have been studying? could we have been studying? could you have been studying? could they have been studying?

Interro-negative form

Simple form	V-ing form
could I not study? could you not study? could she not study? could we not study? could you not study? could they not study?	could I not be studying? could you not be studying? could she not be studying? could we not be studying? could you not be studying? could they not be studying?
Perfect	V-ing perfect
could I not have studied? could you not have studied? could she not have studied? could we not have studied? could you not have studied? could they not have studied?	could I not have been studying? could you not have been studying? could she not have been studying? could we not have been studying? could you not have been studying? could they not have been studying?