I can complete you can complete he can complete we can complete you can complete they can complete
V-ing form
I can be completing you can be completing he can be completing we can be completing you can be completing they can be completing
Perfect
I can have completed you can have completed he can have completed we can have completed you can have completed they can have completed
V-ing perfect
I can have been completing you can have been completing he can have been completing we can have been completing you can have been completing they can have been completing
Negation
Simple form
I cannot complete you cannot complete he cannot complete we cannot complete you cannot complete they cannot complete
V-ing form
I cannot be completing you cannot be completing he cannot be completing we cannot be completing you cannot be completing they cannot be completing
Perfect
I cannot have completed you cannot have completed he cannot have completed we cannot have completed you cannot have completed they cannot have completed
V-ing perfect
I cannot have been completing you cannot have been completing he cannot have been completing we cannot have been completing you cannot have been completing they cannot have been completing
Interrogative form
Simple form
can I complete? can you complete? can he complete? can we complete? can you complete? can they complete?
V-ing form
can I be completing? can you be completing? can he be completing? can we be completing? can you be completing? can they be completing?
Perfect
can I have completed? can you have completed? can he have completed? can we have completed? can you have completed? can they have completed?
V-ing perfect
can I have been completing? can you have been completing? can he have been completing? can we have been completing? can you have been completing? can they have been completing?
Interro-negative form
Simple form
can I not complete? can you not complete? can he not complete? can we not complete? can you not complete? can they not complete?
V-ing form
can I not be completing? can you not be completing? can he not be completing? can we not be completing? can you not be completing? can they not be completing?
Perfect
can I not have completed? can you not have completed? can he not have completed? can we not have completed? can you not have completed? can they not have completed?
V-ing perfect
can I not have been completing? can you not have been completing? can he not have been completing? can we not have been completing? can you not have been completing? can they not have been completing?