English verb conjugation
COULD OVERSTUDY

Regular verb: overstudy - overstudied - overstudied

Affirmation

Simple form	V-ing form
I could overstudy you could overstudy he could overstudy we could overstudy you could overstudy they could overstudy	I could be overstudying you could be overstudying he could be overstudying we could be overstudying you could be overstudying they could be overstudying
Perfect	V-ing perfect
I could have overstudied you could have overstudied he could have overstudied we could have overstudied you could have overstudied they could have overstudied	I could have been overstudying you could have been overstudying he could have been overstudying we could have been overstudying you could have been overstudying they could have been overstudying

Negation

Simple form	V-ing form
I couldn't overstudy you couldn't overstudy he couldn't overstudy we couldn't overstudy you couldn't overstudy they couldn't overstudy	I couldn't be overstudying you couldn't be overstudying he couldn't be overstudying we couldn't be overstudying you couldn't be overstudying they couldn't be overstudying
Perfect	V-ing perfect
I couldn't have overstudied you couldn't have overstudied he couldn't have overstudied we couldn't have overstudied you couldn't have overstudied they couldn't have overstudied	I couldn't have been overstudying you couldn't have been overstudying he couldn't have been overstudying we couldn't have been overstudying you couldn't have been overstudying they couldn't have been overstudying

Interrogative form

Simple form	V-ing form
could I overstudy? could you overstudy? could he overstudy? could we overstudy? could you overstudy? could they overstudy?	could I be overstudying? could you be overstudying? could he be overstudying? could we be overstudying? could you be overstudying? could they be overstudying?
Perfect	V-ing perfect
could I have overstudied? could you have overstudied? could he have overstudied? could we have overstudied? could you have overstudied? could they have overstudied?	could I have been overstudying? could you have been overstudying? could he have been overstudying? could we have been overstudying? could you have been overstudying? could they have been overstudying?

Interro-negative form

Simple form	V-ing form
couldn't I overstudy? couldn't you overstudy? couldn't he overstudy? couldn't we overstudy? couldn't you overstudy? couldn't they overstudy?	couldn't I be overstudying? couldn't you be overstudying? couldn't he be overstudying? couldn't we be overstudying? couldn't you be overstudying? couldn't they be overstudying?
Perfect	V-ing perfect
couldn't I have overstudied? couldn't you have overstudied? couldn't he have overstudied? couldn't we have overstudied? couldn't you have overstudied? couldn't they have overstudied?	couldn't I have been overstudying? couldn't you have been overstudying? couldn't he have been overstudying? couldn't we have been overstudying? couldn't you have been overstudying? couldn't they have been overstudying?