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