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