English verb conjugation
MUST COMBINE

Regular verb: combine - combined - combined

Affirmation

Simple form	V-ing form
I must combine you must combine he must combine we must combine you must combine they must combine	I must be combining you must be combining he must be combining we must be combining you must be combining they must be combining
Perfect	V-ing perfect
I must have combined you must have combined he must have combined we must have combined you must have combined they must have combined	I must have been combining you must have been combining he must have been combining we must have been combining you must have been combining they must have been combining

Negation

Simple form	V-ing form
I must not combine you must not combine he must not combine we must not combine you must not combine they must not combine	I must not be combining you must not be combining he must not be combining we must not be combining you must not be combining they must not be combining
Perfect	V-ing perfect
I must not have combined you must not have combined he must not have combined we must not have combined you must not have combined they must not have combined	I must not have been combining you must not have been combining he must not have been combining we must not have been combining you must not have been combining they must not have been combining

Interrogative form

Simple form	V-ing form
must I combine? must you combine? must he combine? must we combine? must you combine? must they combine?	must I be combining? must you be combining? must he be combining? must we be combining? must you be combining? must they be combining?
Perfect	V-ing perfect
must I have combined? must you have combined? must he have combined? must we have combined? must you have combined? must they have combined?	must I have been combining? must you have been combining? must he have been combining? must we have been combining? must you have been combining? must they have been combining?

Interro-negative form

Simple form	V-ing form
must I not combine? must you not combine? must he not combine? must we not combine? must you not combine? must they not combine?	must I not be combining? must you not be combining? must he not be combining? must we not be combining? must you not be combining? must they not be combining?
Perfect	V-ing perfect
must I not have combined? must you not have combined? must he not have combined? must we not have combined? must you not have combined? must they not have combined?	must I not have been combining? must you not have been combining? must he not have been combining? must we not have been combining? must you not have been combining? must they not have been combining?