I can curl you can curl he can curl we can curl you can curl they can curl
V-ing form
I can be curling you can be curling he can be curling we can be curling you can be curling they can be curling
Perfect
I can have curled you can have curled he can have curled we can have curled you can have curled they can have curled
V-ing perfect
I can have been curling you can have been curling he can have been curling we can have been curling you can have been curling they can have been curling
Negation
Simple form
I can't curl you can't curl he can't curl we can't curl you can't curl they can't curl
V-ing form
I can't be curling you can't be curling he can't be curling we can't be curling you can't be curling they can't be curling
Perfect
I can't have curled you can't have curled he can't have curled we can't have curled you can't have curled they can't have curled
V-ing perfect
I can't have been curling you can't have been curling he can't have been curling we can't have been curling you can't have been curling they can't have been curling
Interrogative form
Simple form
can I curl? can you curl? can he curl? can we curl? can you curl? can they curl?
V-ing form
can I be curling? can you be curling? can he be curling? can we be curling? can you be curling? can they be curling?
Perfect
can I have curled? can you have curled? can he have curled? can we have curled? can you have curled? can they have curled?
V-ing perfect
can I have been curling? can you have been curling? can he have been curling? can we have been curling? can you have been curling? can they have been curling?
Interro-negative form
Simple form
can't I curl? can't you curl? can't he curl? can't we curl? can't you curl? can't they curl?
V-ing form
can't I be curling? can't you be curling? can't he be curling? can't we be curling? can't you be curling? can't they be curling?
Perfect
can't I have curled? can't you have curled? can't he have curled? can't we have curled? can't you have curled? can't they have curled?
V-ing perfect
can't I have been curling? can't you have been curling? can't he have been curling? can't we have been curling? can't you have been curling? can't they have been curling?