English verb conjugation
MUST COUCH

Regular verb: couch - couched - couched

Affirmation

Simple form	V-ing form
I must couch you must couch he must couch we must couch you must couch they must couch	I must be couching you must be couching he must be couching we must be couching you must be couching they must be couching
Perfect	V-ing perfect
I must have couched you must have couched he must have couched we must have couched you must have couched they must have couched	I must have been couching you must have been couching he must have been couching we must have been couching you must have been couching they must have been couching

Negation

Simple form	V-ing form
I mustn't couch you mustn't couch he mustn't couch we mustn't couch you mustn't couch they mustn't couch	I mustn't be couching you mustn't be couching he mustn't be couching we mustn't be couching you mustn't be couching they mustn't be couching
Perfect	V-ing perfect
I mustn't have couched you mustn't have couched he mustn't have couched we mustn't have couched you mustn't have couched they mustn't have couched	I mustn't have been couching you mustn't have been couching he mustn't have been couching we mustn't have been couching you mustn't have been couching they mustn't have been couching

Interrogative form

Simple form	V-ing form
must I couch? must you couch? must he couch? must we couch? must you couch? must they couch?	must I be couching? must you be couching? must he be couching? must we be couching? must you be couching? must they be couching?
Perfect	V-ing perfect
must I have couched? must you have couched? must he have couched? must we have couched? must you have couched? must they have couched?	must I have been couching? must you have been couching? must he have been couching? must we have been couching? must you have been couching? must they have been couching?

Interro-negative form

Simple form	V-ing form
mustn't I couch? mustn't you couch? mustn't he couch? mustn't we couch? mustn't you couch? mustn't they couch?	mustn't I be couching? mustn't you be couching? mustn't he be couching? mustn't we be couching? mustn't you be couching? mustn't they be couching?
Perfect	V-ing perfect
mustn't I have couched? mustn't you have couched? mustn't he have couched? mustn't we have couched? mustn't you have couched? mustn't they have couched?	mustn't I have been couching? mustn't you have been couching? mustn't he have been couching? mustn't we have been couching? mustn't you have been couching? mustn't they have been couching?