English verb conjugation
MUST STAPLE

Regular verb: staple - stapled - stapled

Affirmation

Simple form	V-ing form
I must staple you must staple he must staple we must staple you must staple they must staple	I must be stapling you must be stapling he must be stapling we must be stapling you must be stapling they must be stapling
Perfect	V-ing perfect
I must have stapled you must have stapled he must have stapled we must have stapled you must have stapled they must have stapled	I must have been stapling you must have been stapling he must have been stapling we must have been stapling you must have been stapling they must have been stapling

Negation

Simple form	V-ing form
I must not staple you must not staple he must not staple we must not staple you must not staple they must not staple	I must not be stapling you must not be stapling he must not be stapling we must not be stapling you must not be stapling they must not be stapling
Perfect	V-ing perfect
I must not have stapled you must not have stapled he must not have stapled we must not have stapled you must not have stapled they must not have stapled	I must not have been stapling you must not have been stapling he must not have been stapling we must not have been stapling you must not have been stapling they must not have been stapling

Interrogative form

Simple form	V-ing form
must I staple? must you staple? must he staple? must we staple? must you staple? must they staple?	must I be stapling? must you be stapling? must he be stapling? must we be stapling? must you be stapling? must they be stapling?
Perfect	V-ing perfect
must I have stapled? must you have stapled? must he have stapled? must we have stapled? must you have stapled? must they have stapled?	must I have been stapling? must you have been stapling? must he have been stapling? must we have been stapling? must you have been stapling? must they have been stapling?

Interro-negative form

Simple form	V-ing form
must I not staple? must you not staple? must he not staple? must we not staple? must you not staple? must they not staple?	must I not be stapling? must you not be stapling? must he not be stapling? must we not be stapling? must you not be stapling? must they not be stapling?
Perfect	V-ing perfect
must I not have stapled? must you not have stapled? must he not have stapled? must we not have stapled? must you not have stapled? must they not have stapled?	must I not have been stapling? must you not have been stapling? must he not have been stapling? must we not have been stapling? must you not have been stapling? must they not have been stapling?