I can skip you can skip she can skip we can skip you can skip they can skip
V-ing form
I can be skipping you can be skipping she can be skipping we can be skipping you can be skipping they can be skipping
Perfect
I can have skipped you can have skipped she can have skipped we can have skipped you can have skipped they can have skipped
V-ing perfect
I can have been skipping you can have been skipping she can have been skipping we can have been skipping you can have been skipping they can have been skipping
Negation
Simple form
I cannot skip you cannot skip she cannot skip we cannot skip you cannot skip they cannot skip
V-ing form
I cannot be skipping you cannot be skipping she cannot be skipping we cannot be skipping you cannot be skipping they cannot be skipping
Perfect
I cannot have skipped you cannot have skipped she cannot have skipped we cannot have skipped you cannot have skipped they cannot have skipped
V-ing perfect
I cannot have been skipping you cannot have been skipping she cannot have been skipping we cannot have been skipping you cannot have been skipping they cannot have been skipping
Interrogative form
Simple form
can I skip? can you skip? can she skip? can we skip? can you skip? can they skip?
V-ing form
can I be skipping? can you be skipping? can she be skipping? can we be skipping? can you be skipping? can they be skipping?
Perfect
can I have skipped? can you have skipped? can she have skipped? can we have skipped? can you have skipped? can they have skipped?
V-ing perfect
can I have been skipping? can you have been skipping? can she have been skipping? can we have been skipping? can you have been skipping? can they have been skipping?
Interro-negative form
Simple form
can I not skip? can you not skip? can she not skip? can we not skip? can you not skip? can they not skip?
V-ing form
can I not be skipping? can you not be skipping? can she not be skipping? can we not be skipping? can you not be skipping? can they not be skipping?
Perfect
can I not have skipped? can you not have skipped? can she not have skipped? can we not have skipped? can you not have skipped? can they not have skipped?
V-ing perfect
can I not have been skipping? can you not have been skipping? can she not have been skipping? can we not have been skipping? can you not have been skipping? can they not have been skipping?