English verb conjugation
COULD QUIZ

Regular verb: quiz - quizzed - quizzed

Affirmation

Simple form	V-ing form
I could quiz you could quiz he could quiz we could quiz you could quiz they could quiz	I could be quizzing you could be quizzing he could be quizzing we could be quizzing you could be quizzing they could be quizzing
Perfect	V-ing perfect
I could have quizzed you could have quizzed he could have quizzed we could have quizzed you could have quizzed they could have quizzed	I could have been quizzing you could have been quizzing he could have been quizzing we could have been quizzing you could have been quizzing they could have been quizzing

Negation

Simple form	V-ing form
I could not quiz you could not quiz he could not quiz we could not quiz you could not quiz they could not quiz	I could not be quizzing you could not be quizzing he could not be quizzing we could not be quizzing you could not be quizzing they could not be quizzing
Perfect	V-ing perfect
I could not have quizzed you could not have quizzed he could not have quizzed we could not have quizzed you could not have quizzed they could not have quizzed	I could not have been quizzing you could not have been quizzing he could not have been quizzing we could not have been quizzing you could not have been quizzing they could not have been quizzing

Interrogative form

Simple form	V-ing form
could I quiz? could you quiz? could he quiz? could we quiz? could you quiz? could they quiz?	could I be quizzing? could you be quizzing? could he be quizzing? could we be quizzing? could you be quizzing? could they be quizzing?
Perfect	V-ing perfect
could I have quizzed? could you have quizzed? could he have quizzed? could we have quizzed? could you have quizzed? could they have quizzed?	could I have been quizzing? could you have been quizzing? could he have been quizzing? could we have been quizzing? could you have been quizzing? could they have been quizzing?

Interro-negative form

Simple form	V-ing form
could I not quiz? could you not quiz? could he not quiz? could we not quiz? could you not quiz? could they not quiz?	could I not be quizzing? could you not be quizzing? could he not be quizzing? could we not be quizzing? could you not be quizzing? could they not be quizzing?
Perfect	V-ing perfect
could I not have quizzed? could you not have quizzed? could he not have quizzed? could we not have quizzed? could you not have quizzed? could they not have quizzed?	could I not have been quizzing? could you not have been quizzing? could he not have been quizzing? could we not have been quizzing? could you not have been quizzing? could they not have been quizzing?