English verb conjugation
MUST CRAB

Regular verb: crab - crabbed - crabbed

Affirmation

Simple form	V-ing form
I must crab you must crab he must crab we must crab you must crab they must crab	I must be crabbing you must be crabbing he must be crabbing we must be crabbing you must be crabbing they must be crabbing
Perfect	V-ing perfect
I must have crabbed you must have crabbed he must have crabbed we must have crabbed you must have crabbed they must have crabbed	I must have been crabbing you must have been crabbing he must have been crabbing we must have been crabbing you must have been crabbing they must have been crabbing

Negation

Simple form	V-ing form
I mustn't crab you mustn't crab he mustn't crab we mustn't crab you mustn't crab they mustn't crab	I mustn't be crabbing you mustn't be crabbing he mustn't be crabbing we mustn't be crabbing you mustn't be crabbing they mustn't be crabbing
Perfect	V-ing perfect
I mustn't have crabbed you mustn't have crabbed he mustn't have crabbed we mustn't have crabbed you mustn't have crabbed they mustn't have crabbed	I mustn't have been crabbing you mustn't have been crabbing he mustn't have been crabbing we mustn't have been crabbing you mustn't have been crabbing they mustn't have been crabbing

Interrogative form

Simple form	V-ing form
must I crab? must you crab? must he crab? must we crab? must you crab? must they crab?	must I be crabbing? must you be crabbing? must he be crabbing? must we be crabbing? must you be crabbing? must they be crabbing?
Perfect	V-ing perfect
must I have crabbed? must you have crabbed? must he have crabbed? must we have crabbed? must you have crabbed? must they have crabbed?	must I have been crabbing? must you have been crabbing? must he have been crabbing? must we have been crabbing? must you have been crabbing? must they have been crabbing?

Interro-negative form

Simple form	V-ing form
mustn't I crab? mustn't you crab? mustn't he crab? mustn't we crab? mustn't you crab? mustn't they crab?	mustn't I be crabbing? mustn't you be crabbing? mustn't he be crabbing? mustn't we be crabbing? mustn't you be crabbing? mustn't they be crabbing?
Perfect	V-ing perfect
mustn't I have crabbed? mustn't you have crabbed? mustn't he have crabbed? mustn't we have crabbed? mustn't you have crabbed? mustn't they have crabbed?	mustn't I have been crabbing? mustn't you have been crabbing? mustn't he have been crabbing? mustn't we have been crabbing? mustn't you have been crabbing? mustn't they have been crabbing?