I must smear you must smear she must smear we must smear you must smear they must smear
V-ing form
I must be smearing you must be smearing she must be smearing we must be smearing you must be smearing they must be smearing
Perfect
I must have smeared you must have smeared she 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 she 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 she 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 she 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 she 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 she 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 she smear? must we smear? must you smear? must they smear?
V-ing form
must I be smearing? must you be smearing? must she be smearing? must we be smearing? must you be smearing? must they be smearing?
Perfect
must I have smeared? must you have smeared? must she 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 she 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 she 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 she 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 she 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 she have been smearing? mustn't we have been smearing? mustn't you have been smearing? mustn't they have been smearing?