English verb conjugation
MUST COMBUST

Regular verb: combust - combusted - combusted

Affirmation

Simple form	V-ing form
I must combust you must combust he must combust we must combust you must combust they must combust	I must be combusting you must be combusting he must be combusting we must be combusting you must be combusting they must be combusting
Perfect	V-ing perfect
I must have combusted you must have combusted he must have combusted we must have combusted you must have combusted they must have combusted	I must have been combusting you must have been combusting he must have been combusting we must have been combusting you must have been combusting they must have been combusting

Negation

Simple form	V-ing form
I must not combust you must not combust he must not combust we must not combust you must not combust they must not combust	I must not be combusting you must not be combusting he must not be combusting we must not be combusting you must not be combusting they must not be combusting
Perfect	V-ing perfect
I must not have combusted you must not have combusted he must not have combusted we must not have combusted you must not have combusted they must not have combusted	I must not have been combusting you must not have been combusting he must not have been combusting we must not have been combusting you must not have been combusting they must not have been combusting

Interrogative form

Simple form	V-ing form
must I combust? must you combust? must he combust? must we combust? must you combust? must they combust?	must I be combusting? must you be combusting? must he be combusting? must we be combusting? must you be combusting? must they be combusting?
Perfect	V-ing perfect
must I have combusted? must you have combusted? must he have combusted? must we have combusted? must you have combusted? must they have combusted?	must I have been combusting? must you have been combusting? must he have been combusting? must we have been combusting? must you have been combusting? must they have been combusting?

Interro-negative form

Simple form	V-ing form
must I not combust? must you not combust? must he not combust? must we not combust? must you not combust? must they not combust?	must I not be combusting? must you not be combusting? must he not be combusting? must we not be combusting? must you not be combusting? must they not be combusting?
Perfect	V-ing perfect
must I not have combusted? must you not have combusted? must he not have combusted? must we not have combusted? must you not have combusted? must they not have combusted?	must I not have been combusting? must you not have been combusting? must he not have been combusting? must we not have been combusting? must you not have been combusting? must they not have been combusting?