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