I could taw you could taw she could taw we could taw you could taw they could taw
V-ing form
I could be tawing you could be tawing she could be tawing we could be tawing you could be tawing they could be tawing
Perfect
I could have tawed you could have tawed she could have tawed we could have tawed you could have tawed they could have tawed
V-ing perfect
I could have been tawing you could have been tawing she could have been tawing we could have been tawing you could have been tawing they could have been tawing
Negation
Simple form
I couldn't taw you couldn't taw she couldn't taw we couldn't taw you couldn't taw they couldn't taw
V-ing form
I couldn't be tawing you couldn't be tawing she couldn't be tawing we couldn't be tawing you couldn't be tawing they couldn't be tawing
Perfect
I couldn't have tawed you couldn't have tawed she couldn't have tawed we couldn't have tawed you couldn't have tawed they couldn't have tawed
V-ing perfect
I couldn't have been tawing you couldn't have been tawing she couldn't have been tawing we couldn't have been tawing you couldn't have been tawing they couldn't have been tawing
Interrogative form
Simple form
could I taw? could you taw? could she taw? could we taw? could you taw? could they taw?
V-ing form
could I be tawing? could you be tawing? could she be tawing? could we be tawing? could you be tawing? could they be tawing?
Perfect
could I have tawed? could you have tawed? could she have tawed? could we have tawed? could you have tawed? could they have tawed?
V-ing perfect
could I have been tawing? could you have been tawing? could she have been tawing? could we have been tawing? could you have been tawing? could they have been tawing?
Interro-negative form
Simple form
couldn't I taw? couldn't you taw? couldn't she taw? couldn't we taw? couldn't you taw? couldn't they taw?
V-ing form
couldn't I be tawing? couldn't you be tawing? couldn't she be tawing? couldn't we be tawing? couldn't you be tawing? couldn't they be tawing?
Perfect
couldn't I have tawed? couldn't you have tawed? couldn't she have tawed? couldn't we have tawed? couldn't you have tawed? couldn't they have tawed?
V-ing perfect
couldn't I have been tawing? couldn't you have been tawing? couldn't she have been tawing? couldn't we have been tawing? couldn't you have been tawing? couldn't they have been tawing?