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