I can grate you can grate she can grate we can grate you can grate they can grate
V-ing form
I can be grating you can be grating she can be grating we can be grating you can be grating they can be grating
Perfect
I can have grated you can have grated she can have grated we can have grated you can have grated they can have grated
V-ing perfect
I can have been grating you can have been grating she can have been grating we can have been grating you can have been grating they can have been grating
Negation
Simple form
I cannot grate you cannot grate she cannot grate we cannot grate you cannot grate they cannot grate
V-ing form
I cannot be grating you cannot be grating she cannot be grating we cannot be grating you cannot be grating they cannot be grating
Perfect
I cannot have grated you cannot have grated she cannot have grated we cannot have grated you cannot have grated they cannot have grated
V-ing perfect
I cannot have been grating you cannot have been grating she cannot have been grating we cannot have been grating you cannot have been grating they cannot have been grating
Interrogative form
Simple form
can I grate? can you grate? can she grate? can we grate? can you grate? can they grate?
V-ing form
can I be grating? can you be grating? can she be grating? can we be grating? can you be grating? can they be grating?
Perfect
can I have grated? can you have grated? can she have grated? can we have grated? can you have grated? can they have grated?
V-ing perfect
can I have been grating? can you have been grating? can she have been grating? can we have been grating? can you have been grating? can they have been grating?
Interro-negative form
Simple form
can I not grate? can you not grate? can she not grate? can we not grate? can you not grate? can they not grate?
V-ing form
can I not be grating? can you not be grating? can she not be grating? can we not be grating? can you not be grating? can they not be grating?
Perfect
can I not have grated? can you not have grated? can she not have grated? can we not have grated? can you not have grated? can they not have grated?
V-ing perfect
can I not have been grating? can you not have been grating? can she not have been grating? can we not have been grating? can you not have been grating? can they not have been grating?