I could grit you could grit she could grit we could grit you could grit they could grit
V-ing form
I could be gritting you could be gritting she could be gritting we could be gritting you could be gritting they could be gritting
Perfect
I could have gritted you could have gritted she could have gritted we could have gritted you could have gritted they could have gritted
V-ing perfect
I could have been gritting you could have been gritting she could have been gritting we could have been gritting you could have been gritting they could have been gritting
Negation
Simple form
I could not grit you could not grit she could not grit we could not grit you could not grit they could not grit
V-ing form
I could not be gritting you could not be gritting she could not be gritting we could not be gritting you could not be gritting they could not be gritting
Perfect
I could not have gritted you could not have gritted she could not have gritted we could not have gritted you could not have gritted they could not have gritted
V-ing perfect
I could not have been gritting you could not have been gritting she could not have been gritting we could not have been gritting you could not have been gritting they could not have been gritting
Interrogative form
Simple form
could I grit? could you grit? could she grit? could we grit? could you grit? could they grit?
V-ing form
could I be gritting? could you be gritting? could she be gritting? could we be gritting? could you be gritting? could they be gritting?
Perfect
could I have gritted? could you have gritted? could she have gritted? could we have gritted? could you have gritted? could they have gritted?
V-ing perfect
could I have been gritting? could you have been gritting? could she have been gritting? could we have been gritting? could you have been gritting? could they have been gritting?
Interro-negative form
Simple form
could I not grit? could you not grit? could she not grit? could we not grit? could you not grit? could they not grit?
V-ing form
could I not be gritting? could you not be gritting? could she not be gritting? could we not be gritting? could you not be gritting? could they not be gritting?
Perfect
could I not have gritted? could you not have gritted? could she not have gritted? could we not have gritted? could you not have gritted? could they not have gritted?
V-ing perfect
could I not have been gritting? could you not have been gritting? could she not have been gritting? could we not have been gritting? could you not have been gritting? could they not have been gritting?