English verb conjugation
COULD PROTOTYPE

Regular verb: prototype - prototyped - prototyped

Affirmation

Simple form	V-ing form
I could prototype you could prototype she could prototype we could prototype you could prototype they could prototype	I could be prototyping you could be prototyping she could be prototyping we could be prototyping you could be prototyping they could be prototyping
Perfect	V-ing perfect
I could have prototyped you could have prototyped she could have prototyped we could have prototyped you could have prototyped they could have prototyped	I could have been prototyping you could have been prototyping she could have been prototyping we could have been prototyping you could have been prototyping they could have been prototyping

Negation

Simple form	V-ing form
I could not prototype you could not prototype she could not prototype we could not prototype you could not prototype they could not prototype	I could not be prototyping you could not be prototyping she could not be prototyping we could not be prototyping you could not be prototyping they could not be prototyping
Perfect	V-ing perfect
I could not have prototyped you could not have prototyped she could not have prototyped we could not have prototyped you could not have prototyped they could not have prototyped	I could not have been prototyping you could not have been prototyping she could not have been prototyping we could not have been prototyping you could not have been prototyping they could not have been prototyping

Interrogative form

Simple form	V-ing form
could I prototype? could you prototype? could she prototype? could we prototype? could you prototype? could they prototype?	could I be prototyping? could you be prototyping? could she be prototyping? could we be prototyping? could you be prototyping? could they be prototyping?
Perfect	V-ing perfect
could I have prototyped? could you have prototyped? could she have prototyped? could we have prototyped? could you have prototyped? could they have prototyped?	could I have been prototyping? could you have been prototyping? could she have been prototyping? could we have been prototyping? could you have been prototyping? could they have been prototyping?

Interro-negative form

Simple form	V-ing form
could I not prototype? could you not prototype? could she not prototype? could we not prototype? could you not prototype? could they not prototype?	could I not be prototyping? could you not be prototyping? could she not be prototyping? could we not be prototyping? could you not be prototyping? could they not be prototyping?
Perfect	V-ing perfect
could I not have prototyped? could you not have prototyped? could she not have prototyped? could we not have prototyped? could you not have prototyped? could they not have prototyped?	could I not have been prototyping? could you not have been prototyping? could she not have been prototyping? could we not have been prototyping? could you not have been prototyping? could they not have been prototyping?