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