English verb conjugation
MUST MUTTER

Regular verb: mutter - muttered - muttered

Affirmation

Simple form	V-ing form
I must mutter you must mutter he must mutter we must mutter you must mutter they must mutter	I must be muttering you must be muttering he must be muttering we must be muttering you must be muttering they must be muttering
Perfect	V-ing perfect
I must have muttered you must have muttered he must have muttered we must have muttered you must have muttered they must have muttered	I must have been muttering you must have been muttering he must have been muttering we must have been muttering you must have been muttering they must have been muttering

Negation

Simple form	V-ing form
I must not mutter you must not mutter he must not mutter we must not mutter you must not mutter they must not mutter	I must not be muttering you must not be muttering he must not be muttering we must not be muttering you must not be muttering they must not be muttering
Perfect	V-ing perfect
I must not have muttered you must not have muttered he must not have muttered we must not have muttered you must not have muttered they must not have muttered	I must not have been muttering you must not have been muttering he must not have been muttering we must not have been muttering you must not have been muttering they must not have been muttering

Interrogative form

Simple form	V-ing form
must I mutter? must you mutter? must he mutter? must we mutter? must you mutter? must they mutter?	must I be muttering? must you be muttering? must he be muttering? must we be muttering? must you be muttering? must they be muttering?
Perfect	V-ing perfect
must I have muttered? must you have muttered? must he have muttered? must we have muttered? must you have muttered? must they have muttered?	must I have been muttering? must you have been muttering? must he have been muttering? must we have been muttering? must you have been muttering? must they have been muttering?

Interro-negative form

Simple form	V-ing form
must I not mutter? must you not mutter? must he not mutter? must we not mutter? must you not mutter? must they not mutter?	must I not be muttering? must you not be muttering? must he not be muttering? must we not be muttering? must you not be muttering? must they not be muttering?
Perfect	V-ing perfect
must I not have muttered? must you not have muttered? must he not have muttered? must we not have muttered? must you not have muttered? must they not have muttered?	must I not have been muttering? must you not have been muttering? must he not have been muttering? must we not have been muttering? must you not have been muttering? must they not have been muttering?