I could lucubrate you could lucubrate he could lucubrate we could lucubrate you could lucubrate they could lucubrate
V-ing form
I could be lucubrating you could be lucubrating he could be lucubrating we could be lucubrating you could be lucubrating they could be lucubrating
Perfect
I could have lucubrated you could have lucubrated he could have lucubrated we could have lucubrated you could have lucubrated they could have lucubrated
V-ing perfect
I could have been lucubrating you could have been lucubrating he could have been lucubrating we could have been lucubrating you could have been lucubrating they could have been lucubrating
Negation
Simple form
I could not lucubrate you could not lucubrate he could not lucubrate we could not lucubrate you could not lucubrate they could not lucubrate
V-ing form
I could not be lucubrating you could not be lucubrating he could not be lucubrating we could not be lucubrating you could not be lucubrating they could not be lucubrating
Perfect
I could not have lucubrated you could not have lucubrated he could not have lucubrated we could not have lucubrated you could not have lucubrated they could not have lucubrated
V-ing perfect
I could not have been lucubrating you could not have been lucubrating he could not have been lucubrating we could not have been lucubrating you could not have been lucubrating they could not have been lucubrating
Interrogative form
Simple form
could I lucubrate? could you lucubrate? could he lucubrate? could we lucubrate? could you lucubrate? could they lucubrate?
V-ing form
could I be lucubrating? could you be lucubrating? could he be lucubrating? could we be lucubrating? could you be lucubrating? could they be lucubrating?
Perfect
could I have lucubrated? could you have lucubrated? could he have lucubrated? could we have lucubrated? could you have lucubrated? could they have lucubrated?
V-ing perfect
could I have been lucubrating? could you have been lucubrating? could he have been lucubrating? could we have been lucubrating? could you have been lucubrating? could they have been lucubrating?
Interro-negative form
Simple form
could I not lucubrate? could you not lucubrate? could he not lucubrate? could we not lucubrate? could you not lucubrate? could they not lucubrate?
V-ing form
could I not be lucubrating? could you not be lucubrating? could he not be lucubrating? could we not be lucubrating? could you not be lucubrating? could they not be lucubrating?
Perfect
could I not have lucubrated? could you not have lucubrated? could he not have lucubrated? could we not have lucubrated? could you not have lucubrated? could they not have lucubrated?
V-ing perfect
could I not have been lucubrating? could you not have been lucubrating? could he not have been lucubrating? could we not have been lucubrating? could you not have been lucubrating? could they not have been lucubrating?