could clunk
Regular verb: clunk - clunked- clunked

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I could clunk
you could clunk
she could clunk
we could clunk
you could clunk
they could clunk 	I could be clunking
you could be clunking
she could be clunking
we could be clunking
you could be clunking
they could be clunking	I could have clunked
you could have clunked
she could have clunked
we could have clunked
you could have clunked
they could have clunked	I could have been clunking
you could have been clunking
she could have been clunking
we could have been clunking
you could have been clunking
they could have been clunking	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I could not clunk
you could not clunk
she could not clunk
we could not clunk
you could not clunk
they could not clunk 	I could not be clunking
you could not be clunking
she could not be clunking
we could not be clunking
you could not be clunking
they could not be clunking	I could not have clunked
you could not have clunked
she could not have clunked
we could not have clunked
you could not have clunked
they could not have clunked	I could not have been clunking
you could not have been clunking
she could not have been clunking
we could not have been clunking
you could not have been clunking
they could not have been clunking	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
could I clunk?
could you clunk?
could she clunk?
could we clunk?
could you clunk?
could they clunk? 	could I be clunking?
could you be clunking?
could she be clunking?
could we be clunking?
could you be clunking?
could they be clunking? 	could I have clunked?
could you have clunked?
could she have clunked?
could we have clunked?
could you have clunked?
could they have clunked? 	could I have been clunking?
could you have been clunking?
could she have been clunking?
could we have been clunking?
could you have been clunking?
could they have been clunking? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
could I not clunk?
could you not clunk?
could she not clunk?
could we not clunk?
could you not clunk?
could they not clunk? 	could I not be clunking?
could you not be clunking?
could she not be clunking?
could we not be clunking?
could you not be clunking?
could they not be clunking? 	could I not have clunked?
could you not have clunked?
could she not have clunked?
could we not have clunked?
could you not have clunked?
could they not have clunked? 	could I not have been clunking?
could you not have been clunking?
could she not have been clunking?
could we not have been clunking?
could you not have been clunking?
could they not have been clunking?