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