I can scan you can scan he can scan we can scan you can scan they can scan
V-ing form
I can be scanning you can be scanning he can be scanning we can be scanning you can be scanning they can be scanning
Perfect
I can have scanned you can have scanned he can have scanned we can have scanned you can have scanned they can have scanned
V-ing perfect
I can have been scanning you can have been scanning he can have been scanning we can have been scanning you can have been scanning they can have been scanning
Negation
Simple form
I cannot scan you cannot scan he cannot scan we cannot scan you cannot scan they cannot scan
V-ing form
I cannot be scanning you cannot be scanning he cannot be scanning we cannot be scanning you cannot be scanning they cannot be scanning
Perfect
I cannot have scanned you cannot have scanned he cannot have scanned we cannot have scanned you cannot have scanned they cannot have scanned
V-ing perfect
I cannot have been scanning you cannot have been scanning he cannot have been scanning we cannot have been scanning you cannot have been scanning they cannot have been scanning
Interrogative form
Simple form
can I scan? can you scan? can he scan? can we scan? can you scan? can they scan?
V-ing form
can I be scanning? can you be scanning? can he be scanning? can we be scanning? can you be scanning? can they be scanning?
Perfect
can I have scanned? can you have scanned? can he have scanned? can we have scanned? can you have scanned? can they have scanned?
V-ing perfect
can I have been scanning? can you have been scanning? can he have been scanning? can we have been scanning? can you have been scanning? can they have been scanning?
Interro-negative form
Simple form
can I not scan? can you not scan? can he not scan? can we not scan? can you not scan? can they not scan?
V-ing form
can I not be scanning? can you not be scanning? can he not be scanning? can we not be scanning? can you not be scanning? can they not be scanning?
Perfect
can I not have scanned? can you not have scanned? can he not have scanned? can we not have scanned? can you not have scanned? can they not have scanned?
V-ing perfect
can I not have been scanning? can you not have been scanning? can he not have been scanning? can we not have been scanning? can you not have been scanning? can they not have been scanning?