English verb conjugation
COULD GROSS

Regular verb: gross - grossed - grossed

Affirmation

Simple form	V-ing form
I could gross you could gross he could gross we could gross you could gross they could gross	I could be grossing you could be grossing he could be grossing we could be grossing you could be grossing they could be grossing
Perfect	V-ing perfect
I could have grossed you could have grossed he could have grossed we could have grossed you could have grossed they could have grossed	I could have been grossing you could have been grossing he could have been grossing we could have been grossing you could have been grossing they could have been grossing

Negation

Simple form	V-ing form
I could not gross you could not gross he could not gross we could not gross you could not gross they could not gross	I could not be grossing you could not be grossing he could not be grossing we could not be grossing you could not be grossing they could not be grossing
Perfect	V-ing perfect
I could not have grossed you could not have grossed he could not have grossed we could not have grossed you could not have grossed they could not have grossed	I could not have been grossing you could not have been grossing he could not have been grossing we could not have been grossing you could not have been grossing they could not have been grossing

Interrogative form

Simple form	V-ing form
could I gross? could you gross? could he gross? could we gross? could you gross? could they gross?	could I be grossing? could you be grossing? could he be grossing? could we be grossing? could you be grossing? could they be grossing?
Perfect	V-ing perfect
could I have grossed? could you have grossed? could he have grossed? could we have grossed? could you have grossed? could they have grossed?	could I have been grossing? could you have been grossing? could he have been grossing? could we have been grossing? could you have been grossing? could they have been grossing?

Interro-negative form

Simple form	V-ing form
could I not gross? could you not gross? could he not gross? could we not gross? could you not gross? could they not gross?	could I not be grossing? could you not be grossing? could he not be grossing? could we not be grossing? could you not be grossing? could they not be grossing?
Perfect	V-ing perfect
could I not have grossed? could you not have grossed? could he not have grossed? could we not have grossed? could you not have grossed? could they not have grossed?	could I not have been grossing? could you not have been grossing? could he not have been grossing? could we not have been grossing? could you not have been grossing? could they not have been grossing?