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