must clunk
Regular verb: clunk - clunked- clunked

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

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

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

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