I can keen you can keen she can keen we can keen you can keen they can keen
V-ing form
I can be keening you can be keening she can be keening we can be keening you can be keening they can be keening
Perfect
I can have keened you can have keened she can have keened we can have keened you can have keened they can have keened
V-ing perfect
I can have been keening you can have been keening she can have been keening we can have been keening you can have been keening they can have been keening
Negation
Simple form
I cannot keen you cannot keen she cannot keen we cannot keen you cannot keen they cannot keen
V-ing form
I cannot be keening you cannot be keening she cannot be keening we cannot be keening you cannot be keening they cannot be keening
Perfect
I cannot have keened you cannot have keened she cannot have keened we cannot have keened you cannot have keened they cannot have keened
V-ing perfect
I cannot have been keening you cannot have been keening she cannot have been keening we cannot have been keening you cannot have been keening they cannot have been keening
Interrogative form
Simple form
can I keen? can you keen? can she keen? can we keen? can you keen? can they keen?
V-ing form
can I be keening? can you be keening? can she be keening? can we be keening? can you be keening? can they be keening?
Perfect
can I have keened? can you have keened? can she have keened? can we have keened? can you have keened? can they have keened?
V-ing perfect
can I have been keening? can you have been keening? can she have been keening? can we have been keening? can you have been keening? can they have been keening?
Interro-negative form
Simple form
can I not keen? can you not keen? can she not keen? can we not keen? can you not keen? can they not keen?
V-ing form
can I not be keening? can you not be keening? can she not be keening? can we not be keening? can you not be keening? can they not be keening?
Perfect
can I not have keened? can you not have keened? can she not have keened? can we not have keened? can you not have keened? can they not have keened?
V-ing perfect
can I not have been keening? can you not have been keening? can she not have been keening? can we not have been keening? can you not have been keening? can they not have been keening?