can keen
Regular verb: keen - keened- keened

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I can keen
you can keen
she can keen
we can keen
you can keen
they can keen 	I can be keening
you can be keening
she can be keening
we can be keening
you can be keening
they can be keening	I can have keened
you can have keened
she can have keened
we can have keened
you can have keened
they can have keened	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 	V-ing form 	Perfect 	V-ing perfect 	
I cannot keen
you cannot keen
she cannot keen
we cannot keen
you cannot keen
they cannot keen 	I cannot be keening
you cannot be keening
she cannot be keening
we cannot be keening
you cannot be keening
they cannot be keening	I cannot have keened
you cannot have keened
she cannot have keened
we cannot have keened
you cannot have keened
they cannot have keened	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 	V-ing form 	Perfect 	V-ing perfect 	
can I keen?
can you keen?
can she keen?
can we keen?
can you keen?
can they keen? 	can I be keening?
can you be keening?
can she be keening?
can we be keening?
can you be keening?
can they be keening? 	can I have keened?
can you have keened?
can she have keened?
can we have keened?
can you have keened?
can they have keened? 	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 	V-ing form 	Perfect 	V-ing perfect 	
can I not keen?
can you not keen?
can she not keen?
can we not keen?
can you not keen?
can they not keen? 	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? 	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? 	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?