I must offîceii you must offîceii he must offîceii we must offîceii you must offîceii they must offîceii
V-ing form
I must be offîceiiing you must be offîceiiing he must be offîceiiing we must be offîceiiing you must be offîceiiing they must be offîceiiing
Perfect
I must have offîceiied you must have offîceiied he must have offîceiied we must have offîceiied you must have offîceiied they must have offîceiied
V-ing perfect
I must have been offîceiiing you must have been offîceiiing he must have been offîceiiing we must have been offîceiiing you must have been offîceiiing they must have been offîceiiing
Negation
Simple form
I mustn't offîceii you mustn't offîceii he mustn't offîceii we mustn't offîceii you mustn't offîceii they mustn't offîceii
V-ing form
I mustn't be offîceiiing you mustn't be offîceiiing he mustn't be offîceiiing we mustn't be offîceiiing you mustn't be offîceiiing they mustn't be offîceiiing
Perfect
I mustn't have offîceiied you mustn't have offîceiied he mustn't have offîceiied we mustn't have offîceiied you mustn't have offîceiied they mustn't have offîceiied
V-ing perfect
I mustn't have been offîceiiing you mustn't have been offîceiiing he mustn't have been offîceiiing we mustn't have been offîceiiing you mustn't have been offîceiiing they mustn't have been offîceiiing
Interrogative form
Simple form
must I offîceii? must you offîceii? must he offîceii? must we offîceii? must you offîceii? must they offîceii?
V-ing form
must I be offîceiiing? must you be offîceiiing? must he be offîceiiing? must we be offîceiiing? must you be offîceiiing? must they be offîceiiing?
Perfect
must I have offîceiied? must you have offîceiied? must he have offîceiied? must we have offîceiied? must you have offîceiied? must they have offîceiied?
V-ing perfect
must I have been offîceiiing? must you have been offîceiiing? must he have been offîceiiing? must we have been offîceiiing? must you have been offîceiiing? must they have been offîceiiing?
Interro-negative form
Simple form
mustn't I offîceii? mustn't you offîceii? mustn't he offîceii? mustn't we offîceii? mustn't you offîceii? mustn't they offîceii?
V-ing form
mustn't I be offîceiiing? mustn't you be offîceiiing? mustn't he be offîceiiing? mustn't we be offîceiiing? mustn't you be offîceiiing? mustn't they be offîceiiing?
Perfect
mustn't I have offîceiied? mustn't you have offîceiied? mustn't he have offîceiied? mustn't we have offîceiied? mustn't you have offîceiied? mustn't they have offîceiied?
V-ing perfect
mustn't I have been offîceiiing? mustn't you have been offîceiiing? mustn't he have been offîceiiing? mustn't we have been offîceiiing? mustn't you have been offîceiiing? mustn't they have been offîceiiing?