English verb conjugation
MUST HARDEN

Regular verb: harden - hardened - hardened

Affirmation

Simple form	V-ing form
I must harden you must harden she must harden we must harden you must harden they must harden	I must be hardening you must be hardening she must be hardening we must be hardening you must be hardening they must be hardening
Perfect	V-ing perfect
I must have hardened you must have hardened she must have hardened we must have hardened you must have hardened they must have hardened	I must have been hardening you must have been hardening she must have been hardening we must have been hardening you must have been hardening they must have been hardening

Negation

Simple form	V-ing form
I must not harden you must not harden she must not harden we must not harden you must not harden they must not harden	I must not be hardening you must not be hardening she must not be hardening we must not be hardening you must not be hardening they must not be hardening
Perfect	V-ing perfect
I must not have hardened you must not have hardened she must not have hardened we must not have hardened you must not have hardened they must not have hardened	I must not have been hardening you must not have been hardening she must not have been hardening we must not have been hardening you must not have been hardening they must not have been hardening

Interrogative form

Simple form	V-ing form
must I harden? must you harden? must she harden? must we harden? must you harden? must they harden?	must I be hardening? must you be hardening? must she be hardening? must we be hardening? must you be hardening? must they be hardening?
Perfect	V-ing perfect
must I have hardened? must you have hardened? must she have hardened? must we have hardened? must you have hardened? must they have hardened?	must I have been hardening? must you have been hardening? must she have been hardening? must we have been hardening? must you have been hardening? must they have been hardening?

Interro-negative form

Simple form	V-ing form
must I not harden? must you not harden? must she not harden? must we not harden? must you not harden? must they not harden?	must I not be hardening? must you not be hardening? must she not be hardening? must we not be hardening? must you not be hardening? must they not be hardening?
Perfect	V-ing perfect
must I not have hardened? must you not have hardened? must she not have hardened? must we not have hardened? must you not have hardened? must they not have hardened?	must I not have been hardening? must you not have been hardening? must she not have been hardening? must we not have been hardening? must you not have been hardening? must they not have been hardening?