English verb conjugation
MUST CONTAIN

Regular verb: contain - contained - contained

Affirmation

Simple form	V-ing form
I must contain you must contain he must contain we must contain you must contain they must contain	I must be containing you must be containing he must be containing we must be containing you must be containing they must be containing
Perfect	V-ing perfect
I must have contained you must have contained he must have contained we must have contained you must have contained they must have contained	I must have been containing you must have been containing he must have been containing we must have been containing you must have been containing they must have been containing

Negation

Simple form	V-ing form
I must not contain you must not contain he must not contain we must not contain you must not contain they must not contain	I must not be containing you must not be containing he must not be containing we must not be containing you must not be containing they must not be containing
Perfect	V-ing perfect
I must not have contained you must not have contained he must not have contained we must not have contained you must not have contained they must not have contained	I must not have been containing you must not have been containing he must not have been containing we must not have been containing you must not have been containing they must not have been containing

Interrogative form

Simple form	V-ing form
must I contain? must you contain? must he contain? must we contain? must you contain? must they contain?	must I be containing? must you be containing? must he be containing? must we be containing? must you be containing? must they be containing?
Perfect	V-ing perfect
must I have contained? must you have contained? must he have contained? must we have contained? must you have contained? must they have contained?	must I have been containing? must you have been containing? must he have been containing? must we have been containing? must you have been containing? must they have been containing?

Interro-negative form

Simple form	V-ing form
must I not contain? must you not contain? must he not contain? must we not contain? must you not contain? must they not contain?	must I not be containing? must you not be containing? must he not be containing? must we not be containing? must you not be containing? must they not be containing?
Perfect	V-ing perfect
must I not have contained? must you not have contained? must he not have contained? must we not have contained? must you not have contained? must they not have contained?	must I not have been containing? must you not have been containing? must he not have been containing? must we not have been containing? must you not have been containing? must they not have been containing?