English verb conjugation
MUST FROG

Regular verb: frog - froged - froged

Affirmation

Simple form	V-ing form
I must frog you must frog he must frog we must frog you must frog they must frog	I must be froging you must be froging he must be froging we must be froging you must be froging they must be froging
Perfect	V-ing perfect
I must have froged you must have froged he must have froged we must have froged you must have froged they must have froged	I must have been froging you must have been froging he must have been froging we must have been froging you must have been froging they must have been froging

Negation

Simple form	V-ing form
I mustn't frog you mustn't frog he mustn't frog we mustn't frog you mustn't frog they mustn't frog	I mustn't be froging you mustn't be froging he mustn't be froging we mustn't be froging you mustn't be froging they mustn't be froging
Perfect	V-ing perfect
I mustn't have froged you mustn't have froged he mustn't have froged we mustn't have froged you mustn't have froged they mustn't have froged	I mustn't have been froging you mustn't have been froging he mustn't have been froging we mustn't have been froging you mustn't have been froging they mustn't have been froging

Interrogative form

Simple form	V-ing form
must I frog? must you frog? must he frog? must we frog? must you frog? must they frog?	must I be froging? must you be froging? must he be froging? must we be froging? must you be froging? must they be froging?
Perfect	V-ing perfect
must I have froged? must you have froged? must he have froged? must we have froged? must you have froged? must they have froged?	must I have been froging? must you have been froging? must he have been froging? must we have been froging? must you have been froging? must they have been froging?

Interro-negative form

Simple form	V-ing form
mustn't I frog? mustn't you frog? mustn't he frog? mustn't we frog? mustn't you frog? mustn't they frog?	mustn't I be froging? mustn't you be froging? mustn't he be froging? mustn't we be froging? mustn't you be froging? mustn't they be froging?
Perfect	V-ing perfect
mustn't I have froged? mustn't you have froged? mustn't he have froged? mustn't we have froged? mustn't you have froged? mustn't they have froged?	mustn't I have been froging? mustn't you have been froging? mustn't he have been froging? mustn't we have been froging? mustn't you have been froging? mustn't they have been froging?