I can whiten you can whiten she can whiten we can whiten you can whiten they can whiten
V-ing form
I can be whitening you can be whitening she can be whitening we can be whitening you can be whitening they can be whitening
Perfect
I can have whitened you can have whitened she can have whitened we can have whitened you can have whitened they can have whitened
V-ing perfect
I can have been whitening you can have been whitening she can have been whitening we can have been whitening you can have been whitening they can have been whitening
Negation
Simple form
I cannot whiten you cannot whiten she cannot whiten we cannot whiten you cannot whiten they cannot whiten
V-ing form
I cannot be whitening you cannot be whitening she cannot be whitening we cannot be whitening you cannot be whitening they cannot be whitening
Perfect
I cannot have whitened you cannot have whitened she cannot have whitened we cannot have whitened you cannot have whitened they cannot have whitened
V-ing perfect
I cannot have been whitening you cannot have been whitening she cannot have been whitening we cannot have been whitening you cannot have been whitening they cannot have been whitening
Interrogative form
Simple form
can I whiten? can you whiten? can she whiten? can we whiten? can you whiten? can they whiten?
V-ing form
can I be whitening? can you be whitening? can she be whitening? can we be whitening? can you be whitening? can they be whitening?
Perfect
can I have whitened? can you have whitened? can she have whitened? can we have whitened? can you have whitened? can they have whitened?
V-ing perfect
can I have been whitening? can you have been whitening? can she have been whitening? can we have been whitening? can you have been whitening? can they have been whitening?
Interro-negative form
Simple form
can I not whiten? can you not whiten? can she not whiten? can we not whiten? can you not whiten? can they not whiten?
V-ing form
can I not be whitening? can you not be whitening? can she not be whitening? can we not be whitening? can you not be whitening? can they not be whitening?
Perfect
can I not have whitened? can you not have whitened? can she not have whitened? can we not have whitened? can you not have whitened? can they not have whitened?
V-ing perfect
can I not have been whitening? can you not have been whitening? can she not have been whitening? can we not have been whitening? can you not have been whitening? can they not have been whitening?