I can harp you can harp he can harp we can harp you can harp they can harp
V-ing form
I can be harping you can be harping he can be harping we can be harping you can be harping they can be harping
Perfect
I can have harped you can have harped he can have harped we can have harped you can have harped they can have harped
V-ing perfect
I can have been harping you can have been harping he can have been harping we can have been harping you can have been harping they can have been harping
Negation
Simple form
I can't harp you can't harp he can't harp we can't harp you can't harp they can't harp
V-ing form
I can't be harping you can't be harping he can't be harping we can't be harping you can't be harping they can't be harping
Perfect
I can't have harped you can't have harped he can't have harped we can't have harped you can't have harped they can't have harped
V-ing perfect
I can't have been harping you can't have been harping he can't have been harping we can't have been harping you can't have been harping they can't have been harping
Interrogative form
Simple form
can I harp? can you harp? can he harp? can we harp? can you harp? can they harp?
V-ing form
can I be harping? can you be harping? can he be harping? can we be harping? can you be harping? can they be harping?
Perfect
can I have harped? can you have harped? can he have harped? can we have harped? can you have harped? can they have harped?
V-ing perfect
can I have been harping? can you have been harping? can he have been harping? can we have been harping? can you have been harping? can they have been harping?
Interro-negative form
Simple form
can't I harp? can't you harp? can't he harp? can't we harp? can't you harp? can't they harp?
V-ing form
can't I be harping? can't you be harping? can't he be harping? can't we be harping? can't you be harping? can't they be harping?
Perfect
can't I have harped? can't you have harped? can't he have harped? can't we have harped? can't you have harped? can't they have harped?
V-ing perfect
can't I have been harping? can't you have been harping? can't he have been harping? can't we have been harping? can't you have been harping? can't they have been harping?