I can swear you can swear he can swear we can swear you can swear they can swear
V-ing form
I can be swearing you can be swearing he can be swearing we can be swearing you can be swearing they can be swearing
Perfect
I can have sworn you can have sworn he can have sworn we can have sworn you can have sworn they can have sworn
V-ing perfect
I can have been swearing you can have been swearing he can have been swearing we can have been swearing you can have been swearing they can have been swearing
Negation
Simple form
I can't swear you can't swear he can't swear we can't swear you can't swear they can't swear
V-ing form
I can't be swearing you can't be swearing he can't be swearing we can't be swearing you can't be swearing they can't be swearing
Perfect
I can't have sworn you can't have sworn he can't have sworn we can't have sworn you can't have sworn they can't have sworn
V-ing perfect
I can't have been swearing you can't have been swearing he can't have been swearing we can't have been swearing you can't have been swearing they can't have been swearing
Interrogative form
Simple form
can I swear? can you swear? can he swear? can we swear? can you swear? can they swear?
V-ing form
can I be swearing? can you be swearing? can he be swearing? can we be swearing? can you be swearing? can they be swearing?
Perfect
can I have sworn? can you have sworn? can he have sworn? can we have sworn? can you have sworn? can they have sworn?
V-ing perfect
can I have been swearing? can you have been swearing? can he have been swearing? can we have been swearing? can you have been swearing? can they have been swearing?
Interro-negative form
Simple form
can't I swear? can't you swear? can't he swear? can't we swear? can't you swear? can't they swear?
V-ing form
can't I be swearing? can't you be swearing? can't he be swearing? can't we be swearing? can't you be swearing? can't they be swearing?
Perfect
can't I have sworn? can't you have sworn? can't he have sworn? can't we have sworn? can't you have sworn? can't they have sworn?
V-ing perfect
can't I have been swearing? can't you have been swearing? can't he have been swearing? can't we have been swearing? can't you have been swearing? can't they have been swearing?