English verb conjugation
MUST CUCKOO

Regular verb: cuckoo - cuckooed - cuckooed

Affirmation

Simple form	V-ing form
I must cuckoo you must cuckoo he must cuckoo we must cuckoo you must cuckoo they must cuckoo	I must be cuckooing you must be cuckooing he must be cuckooing we must be cuckooing you must be cuckooing they must be cuckooing
Perfect	V-ing perfect
I must have cuckooed you must have cuckooed he must have cuckooed we must have cuckooed you must have cuckooed they must have cuckooed	I must have been cuckooing you must have been cuckooing he must have been cuckooing we must have been cuckooing you must have been cuckooing they must have been cuckooing

Negation

Simple form	V-ing form
I mustn't cuckoo you mustn't cuckoo he mustn't cuckoo we mustn't cuckoo you mustn't cuckoo they mustn't cuckoo	I mustn't be cuckooing you mustn't be cuckooing he mustn't be cuckooing we mustn't be cuckooing you mustn't be cuckooing they mustn't be cuckooing
Perfect	V-ing perfect
I mustn't have cuckooed you mustn't have cuckooed he mustn't have cuckooed we mustn't have cuckooed you mustn't have cuckooed they mustn't have cuckooed	I mustn't have been cuckooing you mustn't have been cuckooing he mustn't have been cuckooing we mustn't have been cuckooing you mustn't have been cuckooing they mustn't have been cuckooing

Interrogative form

Simple form	V-ing form
must I cuckoo? must you cuckoo? must he cuckoo? must we cuckoo? must you cuckoo? must they cuckoo?	must I be cuckooing? must you be cuckooing? must he be cuckooing? must we be cuckooing? must you be cuckooing? must they be cuckooing?
Perfect	V-ing perfect
must I have cuckooed? must you have cuckooed? must he have cuckooed? must we have cuckooed? must you have cuckooed? must they have cuckooed?	must I have been cuckooing? must you have been cuckooing? must he have been cuckooing? must we have been cuckooing? must you have been cuckooing? must they have been cuckooing?

Interro-negative form

Simple form	V-ing form
mustn't I cuckoo? mustn't you cuckoo? mustn't he cuckoo? mustn't we cuckoo? mustn't you cuckoo? mustn't they cuckoo?	mustn't I be cuckooing? mustn't you be cuckooing? mustn't he be cuckooing? mustn't we be cuckooing? mustn't you be cuckooing? mustn't they be cuckooing?
Perfect	V-ing perfect
mustn't I have cuckooed? mustn't you have cuckooed? mustn't he have cuckooed? mustn't we have cuckooed? mustn't you have cuckooed? mustn't they have cuckooed?	mustn't I have been cuckooing? mustn't you have been cuckooing? mustn't he have been cuckooing? mustn't we have been cuckooing? mustn't you have been cuckooing? mustn't they have been cuckooing?