I can backorder you can backorder he can backorder we can backorder you can backorder they can backorder
V-ing form
I can be backordering you can be backordering he can be backordering we can be backordering you can be backordering they can be backordering
Perfect
I can have backordered you can have backordered he can have backordered we can have backordered you can have backordered they can have backordered
V-ing perfect
I can have been backordering you can have been backordering he can have been backordering we can have been backordering you can have been backordering they can have been backordering
Negation
Simple form
I can't backorder you can't backorder he can't backorder we can't backorder you can't backorder they can't backorder
V-ing form
I can't be backordering you can't be backordering he can't be backordering we can't be backordering you can't be backordering they can't be backordering
Perfect
I can't have backordered you can't have backordered he can't have backordered we can't have backordered you can't have backordered they can't have backordered
V-ing perfect
I can't have been backordering you can't have been backordering he can't have been backordering we can't have been backordering you can't have been backordering they can't have been backordering
Interrogative form
Simple form
can I backorder? can you backorder? can he backorder? can we backorder? can you backorder? can they backorder?
V-ing form
can I be backordering? can you be backordering? can he be backordering? can we be backordering? can you be backordering? can they be backordering?
Perfect
can I have backordered? can you have backordered? can he have backordered? can we have backordered? can you have backordered? can they have backordered?
V-ing perfect
can I have been backordering? can you have been backordering? can he have been backordering? can we have been backordering? can you have been backordering? can they have been backordering?
Interro-negative form
Simple form
can't I backorder? can't you backorder? can't he backorder? can't we backorder? can't you backorder? can't they backorder?
V-ing form
can't I be backordering? can't you be backordering? can't he be backordering? can't we be backordering? can't you be backordering? can't they be backordering?
Perfect
can't I have backordered? can't you have backordered? can't he have backordered? can't we have backordered? can't you have backordered? can't they have backordered?
V-ing perfect
can't I have been backordering? can't you have been backordering? can't he have been backordering? can't we have been backordering? can't you have been backordering? can't they have been backordering?