English verb conjugation
MUST INVENT

Regular verb: invent - invented - invented

Affirmation

Simple form	V-ing form
I must invent you must invent she must invent we must invent you must invent they must invent	I must be inventing you must be inventing she must be inventing we must be inventing you must be inventing they must be inventing
Perfect	V-ing perfect
I must have invented you must have invented she must have invented we must have invented you must have invented they must have invented	I must have been inventing you must have been inventing she must have been inventing we must have been inventing you must have been inventing they must have been inventing

Negation

Simple form	V-ing form
I must not invent you must not invent she must not invent we must not invent you must not invent they must not invent	I must not be inventing you must not be inventing she must not be inventing we must not be inventing you must not be inventing they must not be inventing
Perfect	V-ing perfect
I must not have invented you must not have invented she must not have invented we must not have invented you must not have invented they must not have invented	I must not have been inventing you must not have been inventing she must not have been inventing we must not have been inventing you must not have been inventing they must not have been inventing

Interrogative form

Simple form	V-ing form
must I invent? must you invent? must she invent? must we invent? must you invent? must they invent?	must I be inventing? must you be inventing? must she be inventing? must we be inventing? must you be inventing? must they be inventing?
Perfect	V-ing perfect
must I have invented? must you have invented? must she have invented? must we have invented? must you have invented? must they have invented?	must I have been inventing? must you have been inventing? must she have been inventing? must we have been inventing? must you have been inventing? must they have been inventing?

Interro-negative form

Simple form	V-ing form
must I not invent? must you not invent? must she not invent? must we not invent? must you not invent? must they not invent?	must I not be inventing? must you not be inventing? must she not be inventing? must we not be inventing? must you not be inventing? must they not be inventing?
Perfect	V-ing perfect
must I not have invented? must you not have invented? must she not have invented? must we not have invented? must you not have invented? must they not have invented?	must I not have been inventing? must you not have been inventing? must she not have been inventing? must we not have been inventing? must you not have been inventing? must they not have been inventing?