I can scrub you can scrub he can scrub we can scrub you can scrub they can scrub
V-ing form
I can be scrubbing you can be scrubbing he can be scrubbing we can be scrubbing you can be scrubbing they can be scrubbing
Perfect
I can have scrubbed you can have scrubbed he can have scrubbed we can have scrubbed you can have scrubbed they can have scrubbed
V-ing perfect
I can have been scrubbing you can have been scrubbing he can have been scrubbing we can have been scrubbing you can have been scrubbing they can have been scrubbing
Negation
Simple form
I cannot scrub you cannot scrub he cannot scrub we cannot scrub you cannot scrub they cannot scrub
V-ing form
I cannot be scrubbing you cannot be scrubbing he cannot be scrubbing we cannot be scrubbing you cannot be scrubbing they cannot be scrubbing
Perfect
I cannot have scrubbed you cannot have scrubbed he cannot have scrubbed we cannot have scrubbed you cannot have scrubbed they cannot have scrubbed
V-ing perfect
I cannot have been scrubbing you cannot have been scrubbing he cannot have been scrubbing we cannot have been scrubbing you cannot have been scrubbing they cannot have been scrubbing
Interrogative form
Simple form
can I scrub? can you scrub? can he scrub? can we scrub? can you scrub? can they scrub?
V-ing form
can I be scrubbing? can you be scrubbing? can he be scrubbing? can we be scrubbing? can you be scrubbing? can they be scrubbing?
Perfect
can I have scrubbed? can you have scrubbed? can he have scrubbed? can we have scrubbed? can you have scrubbed? can they have scrubbed?
V-ing perfect
can I have been scrubbing? can you have been scrubbing? can he have been scrubbing? can we have been scrubbing? can you have been scrubbing? can they have been scrubbing?
Interro-negative form
Simple form
can I not scrub? can you not scrub? can he not scrub? can we not scrub? can you not scrub? can they not scrub?
V-ing form
can I not be scrubbing? can you not be scrubbing? can he not be scrubbing? can we not be scrubbing? can you not be scrubbing? can they not be scrubbing?
Perfect
can I not have scrubbed? can you not have scrubbed? can he not have scrubbed? can we not have scrubbed? can you not have scrubbed? can they not have scrubbed?
V-ing perfect
can I not have been scrubbing? can you not have been scrubbing? can he not have been scrubbing? can we not have been scrubbing? can you not have been scrubbing? can they not have been scrubbing?