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