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