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