English verb conjugation
COULD DERIVE

Regular verb: derive - derived - derived

Affirmation

Simple form	V-ing form
I could derive you could derive he could derive we could derive you could derive they could derive	I could be deriving you could be deriving he could be deriving we could be deriving you could be deriving they could be deriving
Perfect	V-ing perfect
I could have derived you could have derived he could have derived we could have derived you could have derived they could have derived	I could have been deriving you could have been deriving he could have been deriving we could have been deriving you could have been deriving they could have been deriving

Negation

Simple form	V-ing form
I could not derive you could not derive he could not derive we could not derive you could not derive they could not derive	I could not be deriving you could not be deriving he could not be deriving we could not be deriving you could not be deriving they could not be deriving
Perfect	V-ing perfect
I could not have derived you could not have derived he could not have derived we could not have derived you could not have derived they could not have derived	I could not have been deriving you could not have been deriving he could not have been deriving we could not have been deriving you could not have been deriving they could not have been deriving

Interrogative form

Simple form	V-ing form
could I derive? could you derive? could he derive? could we derive? could you derive? could they derive?	could I be deriving? could you be deriving? could he be deriving? could we be deriving? could you be deriving? could they be deriving?
Perfect	V-ing perfect
could I have derived? could you have derived? could he have derived? could we have derived? could you have derived? could they have derived?	could I have been deriving? could you have been deriving? could he have been deriving? could we have been deriving? could you have been deriving? could they have been deriving?

Interro-negative form

Simple form	V-ing form
could I not derive? could you not derive? could he not derive? could we not derive? could you not derive? could they not derive?	could I not be deriving? could you not be deriving? could he not be deriving? could we not be deriving? could you not be deriving? could they not be deriving?
Perfect	V-ing perfect
could I not have derived? could you not have derived? could he not have derived? could we not have derived? could you not have derived? could they not have derived?	could I not have been deriving? could you not have been deriving? could he not have been deriving? could we not have been deriving? could you not have been deriving? could they not have been deriving?