I must centrifuge you must centrifuge she must centrifuge we must centrifuge you must centrifuge they must centrifuge
V-ing form
I must be centrifuging you must be centrifuging she must be centrifuging we must be centrifuging you must be centrifuging they must be centrifuging
Perfect
I must have centrifuged you must have centrifuged she must have centrifuged we must have centrifuged you must have centrifuged they must have centrifuged
V-ing perfect
I must have been centrifuging you must have been centrifuging she must have been centrifuging we must have been centrifuging you must have been centrifuging they must have been centrifuging
Negation
Simple form
I mustn't centrifuge you mustn't centrifuge she mustn't centrifuge we mustn't centrifuge you mustn't centrifuge they mustn't centrifuge
V-ing form
I mustn't be centrifuging you mustn't be centrifuging she mustn't be centrifuging we mustn't be centrifuging you mustn't be centrifuging they mustn't be centrifuging
Perfect
I mustn't have centrifuged you mustn't have centrifuged she mustn't have centrifuged we mustn't have centrifuged you mustn't have centrifuged they mustn't have centrifuged
V-ing perfect
I mustn't have been centrifuging you mustn't have been centrifuging she mustn't have been centrifuging we mustn't have been centrifuging you mustn't have been centrifuging they mustn't have been centrifuging
Interrogative form
Simple form
must I centrifuge? must you centrifuge? must she centrifuge? must we centrifuge? must you centrifuge? must they centrifuge?
V-ing form
must I be centrifuging? must you be centrifuging? must she be centrifuging? must we be centrifuging? must you be centrifuging? must they be centrifuging?
Perfect
must I have centrifuged? must you have centrifuged? must she have centrifuged? must we have centrifuged? must you have centrifuged? must they have centrifuged?
V-ing perfect
must I have been centrifuging? must you have been centrifuging? must she have been centrifuging? must we have been centrifuging? must you have been centrifuging? must they have been centrifuging?
Interro-negative form
Simple form
mustn't I centrifuge? mustn't you centrifuge? mustn't she centrifuge? mustn't we centrifuge? mustn't you centrifuge? mustn't they centrifuge?
V-ing form
mustn't I be centrifuging? mustn't you be centrifuging? mustn't she be centrifuging? mustn't we be centrifuging? mustn't you be centrifuging? mustn't they be centrifuging?
Perfect
mustn't I have centrifuged? mustn't you have centrifuged? mustn't she have centrifuged? mustn't we have centrifuged? mustn't you have centrifuged? mustn't they have centrifuged?
V-ing perfect
mustn't I have been centrifuging? mustn't you have been centrifuging? mustn't she have been centrifuging? mustn't we have been centrifuging? mustn't you have been centrifuging? mustn't they have been centrifuging?