I must spoil you must spoil she must spoil we must spoil you must spoil they must spoil
V-ing form
I must be spoiling you must be spoiling she must be spoiling we must be spoiling you must be spoiling they must be spoiling
Perfect
I must have spoiled, spoilt you must have spoiled, spoilt she must have spoiled, spoilt we must have spoiled, spoilt you must have spoiled, spoilt they must have spoiled, spoilt
V-ing perfect
I must have been spoiling you must have been spoiling she must have been spoiling we must have been spoiling you must have been spoiling they must have been spoiling
Negation
Simple form
I mustn't spoil you mustn't spoil she mustn't spoil we mustn't spoil you mustn't spoil they mustn't spoil
V-ing form
I mustn't be spoiling you mustn't be spoiling she mustn't be spoiling we mustn't be spoiling you mustn't be spoiling they mustn't be spoiling
Perfect
I mustn't have spoiled, spoilt you mustn't have spoiled, spoilt she mustn't have spoiled, spoilt we mustn't have spoiled, spoilt you mustn't have spoiled, spoilt they mustn't have spoiled, spoilt
V-ing perfect
I mustn't have been spoiling you mustn't have been spoiling she mustn't have been spoiling we mustn't have been spoiling you mustn't have been spoiling they mustn't have been spoiling
Interrogative form
Simple form
must I spoil? must you spoil? must she spoil? must we spoil? must you spoil? must they spoil?
V-ing form
must I be spoiling? must you be spoiling? must she be spoiling? must we be spoiling? must you be spoiling? must they be spoiling?
Perfect
must I have spoiled, spoilt? must you have spoiled, spoilt? must she have spoiled, spoilt? must we have spoiled, spoilt? must you have spoiled, spoilt? must they have spoiled, spoilt?
V-ing perfect
must I have been spoiling? must you have been spoiling? must she have been spoiling? must we have been spoiling? must you have been spoiling? must they have been spoiling?
Interro-negative form
Simple form
mustn't I spoil? mustn't you spoil? mustn't she spoil? mustn't we spoil? mustn't you spoil? mustn't they spoil?
V-ing form
mustn't I be spoiling? mustn't you be spoiling? mustn't she be spoiling? mustn't we be spoiling? mustn't you be spoiling? mustn't they be spoiling?
Perfect
mustn't I have spoiled, spoilt? mustn't you have spoiled, spoilt? mustn't she have spoiled, spoilt? mustn't we have spoiled, spoilt? mustn't you have spoiled, spoilt? mustn't they have spoiled, spoilt?
V-ing perfect
mustn't I have been spoiling? mustn't you have been spoiling? mustn't she have been spoiling? mustn't we have been spoiling? mustn't you have been spoiling? mustn't they have been spoiling?