English verb conjugation
MUST DULL

Regular verb: dull - dulled - dulled

Affirmation

Simple form	V-ing form
I must dull you must dull he must dull we must dull you must dull they must dull	I must be dulling you must be dulling he must be dulling we must be dulling you must be dulling they must be dulling
Perfect	V-ing perfect
I must have dulled you must have dulled he must have dulled we must have dulled you must have dulled they must have dulled	I must have been dulling you must have been dulling he must have been dulling we must have been dulling you must have been dulling they must have been dulling

Negation

Simple form	V-ing form
I mustn't dull you mustn't dull he mustn't dull we mustn't dull you mustn't dull they mustn't dull	I mustn't be dulling you mustn't be dulling he mustn't be dulling we mustn't be dulling you mustn't be dulling they mustn't be dulling
Perfect	V-ing perfect
I mustn't have dulled you mustn't have dulled he mustn't have dulled we mustn't have dulled you mustn't have dulled they mustn't have dulled	I mustn't have been dulling you mustn't have been dulling he mustn't have been dulling we mustn't have been dulling you mustn't have been dulling they mustn't have been dulling

Interrogative form

Simple form	V-ing form
must I dull? must you dull? must he dull? must we dull? must you dull? must they dull?	must I be dulling? must you be dulling? must he be dulling? must we be dulling? must you be dulling? must they be dulling?
Perfect	V-ing perfect
must I have dulled? must you have dulled? must he have dulled? must we have dulled? must you have dulled? must they have dulled?	must I have been dulling? must you have been dulling? must he have been dulling? must we have been dulling? must you have been dulling? must they have been dulling?

Interro-negative form

Simple form	V-ing form
mustn't I dull? mustn't you dull? mustn't he dull? mustn't we dull? mustn't you dull? mustn't they dull?	mustn't I be dulling? mustn't you be dulling? mustn't he be dulling? mustn't we be dulling? mustn't you be dulling? mustn't they be dulling?
Perfect	V-ing perfect
mustn't I have dulled? mustn't you have dulled? mustn't he have dulled? mustn't we have dulled? mustn't you have dulled? mustn't they have dulled?	mustn't I have been dulling? mustn't you have been dulling? mustn't he have been dulling? mustn't we have been dulling? mustn't you have been dulling? mustn't they have been dulling?