I can skip you can skip he can skip we can skip you can skip they can skip
V-ing form
I can be skipping you can be skipping he can be skipping we can be skipping you can be skipping they can be skipping
Perfect
I can have skipped you can have skipped he 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 he 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 he cannot skip we cannot skip you cannot skip they cannot skip
V-ing form
I cannot be skipping you cannot be skipping he cannot be skipping we cannot be skipping you cannot be skipping they cannot be skipping
Perfect
I cannot have skipped you cannot have skipped he 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 he 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 he skip? can we skip? can you skip? can they skip?
V-ing form
can I be skipping? can you be skipping? can he be skipping? can we be skipping? can you be skipping? can they be skipping?
Perfect
can I have skipped? can you have skipped? can he 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 he 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 he 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 he 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 he 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 he not have been skipping? can we not have been skipping? can you not have been skipping? can they not have been skipping?