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