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