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