English verb conjugation
MUST CROON

Regular verb: croon - crooned - crooned

Affirmation

Simple form	V-ing form
I must croon you must croon he must croon we must croon you must croon they must croon	I must be crooning you must be crooning he must be crooning we must be crooning you must be crooning they must be crooning
Perfect	V-ing perfect
I must have crooned you must have crooned he must have crooned we must have crooned you must have crooned they must have crooned	I must have been crooning you must have been crooning he must have been crooning we must have been crooning you must have been crooning they must have been crooning

Negation

Simple form	V-ing form
I mustn't croon you mustn't croon he mustn't croon we mustn't croon you mustn't croon they mustn't croon	I mustn't be crooning you mustn't be crooning he mustn't be crooning we mustn't be crooning you mustn't be crooning they mustn't be crooning
Perfect	V-ing perfect
I mustn't have crooned you mustn't have crooned he mustn't have crooned we mustn't have crooned you mustn't have crooned they mustn't have crooned	I mustn't have been crooning you mustn't have been crooning he mustn't have been crooning we mustn't have been crooning you mustn't have been crooning they mustn't have been crooning

Interrogative form

Simple form	V-ing form
must I croon? must you croon? must he croon? must we croon? must you croon? must they croon?	must I be crooning? must you be crooning? must he be crooning? must we be crooning? must you be crooning? must they be crooning?
Perfect	V-ing perfect
must I have crooned? must you have crooned? must he have crooned? must we have crooned? must you have crooned? must they have crooned?	must I have been crooning? must you have been crooning? must he have been crooning? must we have been crooning? must you have been crooning? must they have been crooning?

Interro-negative form

Simple form	V-ing form
mustn't I croon? mustn't you croon? mustn't he croon? mustn't we croon? mustn't you croon? mustn't they croon?	mustn't I be crooning? mustn't you be crooning? mustn't he be crooning? mustn't we be crooning? mustn't you be crooning? mustn't they be crooning?
Perfect	V-ing perfect
mustn't I have crooned? mustn't you have crooned? mustn't he have crooned? mustn't we have crooned? mustn't you have crooned? mustn't they have crooned?	mustn't I have been crooning? mustn't you have been crooning? mustn't he have been crooning? mustn't we have been crooning? mustn't you have been crooning? mustn't they have been crooning?