must discredit
Regular verb: discredit - discredited- discredited

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I must discredit
you must discredit
he must discredit
we must discredit
you must discredit
they must discredit 	I must be discrediting
you must be discrediting
he must be discrediting
we must be discrediting
you must be discrediting
they must be discrediting	I must have discredited
you must have discredited
he must have discredited
we must have discredited
you must have discredited
they must have discredited	I must have been discrediting
you must have been discrediting
he must have been discrediting
we must have been discrediting
you must have been discrediting
they must have been discrediting	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I mustn't discredit
you mustn't discredit
he mustn't discredit
we mustn't discredit
you mustn't discredit
they mustn't discredit 	I mustn't be discrediting
you mustn't be discrediting
he mustn't be discrediting
we mustn't be discrediting
you mustn't be discrediting
they mustn't be discrediting	I mustn't have discredited
you mustn't have discredited
he mustn't have discredited
we mustn't have discredited
you mustn't have discredited
they mustn't have discredited	I mustn't have been discrediting
you mustn't have been discrediting
he mustn't have been discrediting
we mustn't have been discrediting
you mustn't have been discrediting
they mustn't have been discrediting	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
must I discredit?
must you discredit?
must he discredit?
must we discredit?
must you discredit?
must they discredit? 	must I be discrediting?
must you be discrediting?
must he be discrediting?
must we be discrediting?
must you be discrediting?
must they be discrediting? 	must I have discredited?
must you have discredited?
must he have discredited?
must we have discredited?
must you have discredited?
must they have discredited? 	must I have been discrediting?
must you have been discrediting?
must he have been discrediting?
must we have been discrediting?
must you have been discrediting?
must they have been discrediting? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
mustn't I discredit?
mustn't you discredit?
mustn't he discredit?
mustn't we discredit?
mustn't you discredit?
mustn't they discredit? 	mustn't I be discrediting?
mustn't you be discrediting?
mustn't he be discrediting?
mustn't we be discrediting?
mustn't you be discrediting?
mustn't they be discrediting? 	mustn't I have discredited?
mustn't you have discredited?
mustn't he have discredited?
mustn't we have discredited?
mustn't you have discredited?
mustn't they have discredited? 	mustn't I have been discrediting?
mustn't you have been discrediting?
mustn't he have been discrediting?
mustn't we have been discrediting?
mustn't you have been discrediting?
mustn't they have been discrediting?