I must speak you must speak he must speak we must speak you must speak they must speak
V-ing form
I must be speaking you must be speaking he must be speaking we must be speaking you must be speaking they must be speaking
Perfect
I must have spoken, spoke you must have spoken, spoke he must have spoken, spoke we must have spoken, spoke you must have spoken, spoke they must have spoken, spoke
V-ing perfect
I must have been speaking you must have been speaking he must have been speaking we must have been speaking you must have been speaking they must have been speaking
Negation
Simple form
I mustn't speak you mustn't speak he mustn't speak we mustn't speak you mustn't speak they mustn't speak
V-ing form
I mustn't be speaking you mustn't be speaking he mustn't be speaking we mustn't be speaking you mustn't be speaking they mustn't be speaking
Perfect
I mustn't have spoken, spoke you mustn't have spoken, spoke he mustn't have spoken, spoke we mustn't have spoken, spoke you mustn't have spoken, spoke they mustn't have spoken, spoke
V-ing perfect
I mustn't have been speaking you mustn't have been speaking he mustn't have been speaking we mustn't have been speaking you mustn't have been speaking they mustn't have been speaking
Interrogative form
Simple form
must I speak? must you speak? must he speak? must we speak? must you speak? must they speak?
V-ing form
must I be speaking? must you be speaking? must he be speaking? must we be speaking? must you be speaking? must they be speaking?
Perfect
must I have spoken, spoke? must you have spoken, spoke? must he have spoken, spoke? must we have spoken, spoke? must you have spoken, spoke? must they have spoken, spoke?
V-ing perfect
must I have been speaking? must you have been speaking? must he have been speaking? must we have been speaking? must you have been speaking? must they have been speaking?
Interro-negative form
Simple form
mustn't I speak? mustn't you speak? mustn't he speak? mustn't we speak? mustn't you speak? mustn't they speak?
V-ing form
mustn't I be speaking? mustn't you be speaking? mustn't he be speaking? mustn't we be speaking? mustn't you be speaking? mustn't they be speaking?
Perfect
mustn't I have spoken, spoke? mustn't you have spoken, spoke? mustn't he have spoken, spoke? mustn't we have spoken, spoke? mustn't you have spoken, spoke? mustn't they have spoken, spoke?
V-ing perfect
mustn't I have been speaking? mustn't you have been speaking? mustn't he have been speaking? mustn't we have been speaking? mustn't you have been speaking? mustn't they have been speaking?