I must slay you must slay she must slay we must slay you must slay they must slay
V-ing form
I must be slaying you must be slaying she must be slaying we must be slaying you must be slaying they must be slaying
Perfect
I must have slain you must have slain she must have slain we must have slain you must have slain they must have slain
V-ing perfect
I must have been slaying you must have been slaying she must have been slaying we must have been slaying you must have been slaying they must have been slaying
Negation
Simple form
I mustn't slay you mustn't slay she mustn't slay we mustn't slay you mustn't slay they mustn't slay
V-ing form
I mustn't be slaying you mustn't be slaying she mustn't be slaying we mustn't be slaying you mustn't be slaying they mustn't be slaying
Perfect
I mustn't have slain you mustn't have slain she mustn't have slain we mustn't have slain you mustn't have slain they mustn't have slain
V-ing perfect
I mustn't have been slaying you mustn't have been slaying she mustn't have been slaying we mustn't have been slaying you mustn't have been slaying they mustn't have been slaying
Interrogative form
Simple form
must I slay? must you slay? must she slay? must we slay? must you slay? must they slay?
V-ing form
must I be slaying? must you be slaying? must she be slaying? must we be slaying? must you be slaying? must they be slaying?
Perfect
must I have slain? must you have slain? must she have slain? must we have slain? must you have slain? must they have slain?
V-ing perfect
must I have been slaying? must you have been slaying? must she have been slaying? must we have been slaying? must you have been slaying? must they have been slaying?
Interro-negative form
Simple form
mustn't I slay? mustn't you slay? mustn't she slay? mustn't we slay? mustn't you slay? mustn't they slay?
V-ing form
mustn't I be slaying? mustn't you be slaying? mustn't she be slaying? mustn't we be slaying? mustn't you be slaying? mustn't they be slaying?
Perfect
mustn't I have slain? mustn't you have slain? mustn't she have slain? mustn't we have slain? mustn't you have slain? mustn't they have slain?
V-ing perfect
mustn't I have been slaying? mustn't you have been slaying? mustn't she have been slaying? mustn't we have been slaying? mustn't you have been slaying? mustn't they have been slaying?