I could kart you could kart he could kart we could kart you could kart they could kart
V-ing form
I could be karting you could be karting he could be karting we could be karting you could be karting they could be karting
Perfect
I could have karted you could have karted he could have karted we could have karted you could have karted they could have karted
V-ing perfect
I could have been karting you could have been karting he could have been karting we could have been karting you could have been karting they could have been karting
Negation
Simple form
I couldn't kart you couldn't kart he couldn't kart we couldn't kart you couldn't kart they couldn't kart
V-ing form
I couldn't be karting you couldn't be karting he couldn't be karting we couldn't be karting you couldn't be karting they couldn't be karting
Perfect
I couldn't have karted you couldn't have karted he couldn't have karted we couldn't have karted you couldn't have karted they couldn't have karted
V-ing perfect
I couldn't have been karting you couldn't have been karting he couldn't have been karting we couldn't have been karting you couldn't have been karting they couldn't have been karting
Interrogative form
Simple form
could I kart? could you kart? could he kart? could we kart? could you kart? could they kart?
V-ing form
could I be karting? could you be karting? could he be karting? could we be karting? could you be karting? could they be karting?
Perfect
could I have karted? could you have karted? could he have karted? could we have karted? could you have karted? could they have karted?
V-ing perfect
could I have been karting? could you have been karting? could he have been karting? could we have been karting? could you have been karting? could they have been karting?
Interro-negative form
Simple form
couldn't I kart? couldn't you kart? couldn't he kart? couldn't we kart? couldn't you kart? couldn't they kart?
V-ing form
couldn't I be karting? couldn't you be karting? couldn't he be karting? couldn't we be karting? couldn't you be karting? couldn't they be karting?
Perfect
couldn't I have karted? couldn't you have karted? couldn't he have karted? couldn't we have karted? couldn't you have karted? couldn't they have karted?
V-ing perfect
couldn't I have been karting? couldn't you have been karting? couldn't he have been karting? couldn't we have been karting? couldn't you have been karting? couldn't they have been karting?