can knell
Regular verb: knell - knelled- knelled

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I can knell
you can knell
he can knell
we can knell
you can knell
they can knell 	I can be knelling
you can be knelling
he can be knelling
we can be knelling
you can be knelling
they can be knelling	I can have knelled
you can have knelled
he can have knelled
we can have knelled
you can have knelled
they can have knelled	I can have been knelling
you can have been knelling
he can have been knelling
we can have been knelling
you can have been knelling
they can have been knelling	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I cannot knell
you cannot knell
he cannot knell
we cannot knell
you cannot knell
they cannot knell 	I cannot be knelling
you cannot be knelling
he cannot be knelling
we cannot be knelling
you cannot be knelling
they cannot be knelling	I cannot have knelled
you cannot have knelled
he cannot have knelled
we cannot have knelled
you cannot have knelled
they cannot have knelled	I cannot have been knelling
you cannot have been knelling
he cannot have been knelling
we cannot have been knelling
you cannot have been knelling
they cannot have been knelling	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
can I knell?
can you knell?
can he knell?
can we knell?
can you knell?
can they knell? 	can I be knelling?
can you be knelling?
can he be knelling?
can we be knelling?
can you be knelling?
can they be knelling? 	can I have knelled?
can you have knelled?
can he have knelled?
can we have knelled?
can you have knelled?
can they have knelled? 	can I have been knelling?
can you have been knelling?
can he have been knelling?
can we have been knelling?
can you have been knelling?
can they have been knelling? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
can I not knell?
can you not knell?
can he not knell?
can we not knell?
can you not knell?
can they not knell? 	can I not be knelling?
can you not be knelling?
can he not be knelling?
can we not be knelling?
can you not be knelling?
can they not be knelling? 	can I not have knelled?
can you not have knelled?
can he not have knelled?
can we not have knelled?
can you not have knelled?
can they not have knelled? 	can I not have been knelling?
can you not have been knelling?
can he not have been knelling?
can we not have been knelling?
can you not have been knelling?
can they not have been knelling?