English verb conjugation
COULD DISCOVER

Regular verb: discover - discovered - discovered

Affirmation

Simple form	V-ing form
I could discover you could discover he could discover we could discover you could discover they could discover	I could be discovering you could be discovering he could be discovering we could be discovering you could be discovering they could be discovering
Perfect	V-ing perfect
I could have discovered you could have discovered he could have discovered we could have discovered you could have discovered they could have discovered	I could have been discovering you could have been discovering he could have been discovering we could have been discovering you could have been discovering they could have been discovering

Negation

Simple form	V-ing form
I could not discover you could not discover he could not discover we could not discover you could not discover they could not discover	I could not be discovering you could not be discovering he could not be discovering we could not be discovering you could not be discovering they could not be discovering
Perfect	V-ing perfect
I could not have discovered you could not have discovered he could not have discovered we could not have discovered you could not have discovered they could not have discovered	I could not have been discovering you could not have been discovering he could not have been discovering we could not have been discovering you could not have been discovering they could not have been discovering

Interrogative form

Simple form	V-ing form
could I discover? could you discover? could he discover? could we discover? could you discover? could they discover?	could I be discovering? could you be discovering? could he be discovering? could we be discovering? could you be discovering? could they be discovering?
Perfect	V-ing perfect
could I have discovered? could you have discovered? could he have discovered? could we have discovered? could you have discovered? could they have discovered?	could I have been discovering? could you have been discovering? could he have been discovering? could we have been discovering? could you have been discovering? could they have been discovering?

Interro-negative form

Simple form	V-ing form
could I not discover? could you not discover? could he not discover? could we not discover? could you not discover? could they not discover?	could I not be discovering? could you not be discovering? could he not be discovering? could we not be discovering? could you not be discovering? could they not be discovering?
Perfect	V-ing perfect
could I not have discovered? could you not have discovered? could he not have discovered? could we not have discovered? could you not have discovered? could they not have discovered?	could I not have been discovering? could you not have been discovering? could he not have been discovering? could we not have been discovering? could you not have been discovering? could they not have been discovering?