English verb conjugation
COULD PERCEIVE

Regular verb: perceive - perceived - perceived

Affirmation

Simple form	V-ing form
I could perceive you could perceive he could perceive we could perceive you could perceive they could perceive	I could be perceiving you could be perceiving he could be perceiving we could be perceiving you could be perceiving they could be perceiving
Perfect	V-ing perfect
I could have perceived you could have perceived he could have perceived we could have perceived you could have perceived they could have perceived	I could have been perceiving you could have been perceiving he could have been perceiving we could have been perceiving you could have been perceiving they could have been perceiving

Negation

Simple form	V-ing form
I could not perceive you could not perceive he could not perceive we could not perceive you could not perceive they could not perceive	I could not be perceiving you could not be perceiving he could not be perceiving we could not be perceiving you could not be perceiving they could not be perceiving
Perfect	V-ing perfect
I could not have perceived you could not have perceived he could not have perceived we could not have perceived you could not have perceived they could not have perceived	I could not have been perceiving you could not have been perceiving he could not have been perceiving we could not have been perceiving you could not have been perceiving they could not have been perceiving

Interrogative form

Simple form	V-ing form
could I perceive? could you perceive? could he perceive? could we perceive? could you perceive? could they perceive?	could I be perceiving? could you be perceiving? could he be perceiving? could we be perceiving? could you be perceiving? could they be perceiving?
Perfect	V-ing perfect
could I have perceived? could you have perceived? could he have perceived? could we have perceived? could you have perceived? could they have perceived?	could I have been perceiving? could you have been perceiving? could he have been perceiving? could we have been perceiving? could you have been perceiving? could they have been perceiving?

Interro-negative form

Simple form	V-ing form
could I not perceive? could you not perceive? could he not perceive? could we not perceive? could you not perceive? could they not perceive?	could I not be perceiving? could you not be perceiving? could he not be perceiving? could we not be perceiving? could you not be perceiving? could they not be perceiving?
Perfect	V-ing perfect
could I not have perceived? could you not have perceived? could he not have perceived? could we not have perceived? could you not have perceived? could they not have perceived?	could I not have been perceiving? could you not have been perceiving? could he not have been perceiving? could we not have been perceiving? could you not have been perceiving? could they not have been perceiving?