The Conjugator
English verb conjugation
MUST HAPPEN

Regular verb: happen - happened - happened

Affirmation

Simple form

V-ing form

-
-
it must happen
-
-
-
-
-
it must be happening
-
-
-

Perfect

V-ing perfect

-
-
it must have happened
-
-
-
-
-
it must have been happening
-
-
-

Negation

Simple form

V-ing form

-
-
it must not happen
-
-
-
-
-
it must not be happening
-
-
-

Perfect

V-ing perfect

-
-
it must not have happened
-
-
-
-
-
it must not have been happening
-
-
-

Interrogative form

Simple form

V-ing form

-
-
must it happen?
-
-
-
-
-
must it be happening?
-
-
-

Perfect

V-ing perfect

-
-
must it have happened?
-
-
-
-
-
must it have been happening?
-
-
-

Interro-negative form

Simple form

V-ing form

-
-
must it not happen?
-
-
-
-
-
must it not be happening?
-
-
-

Perfect

V-ing perfect

-
-
must it not have happened?
-
-
-
-
-
must it not have been happening?
-
-
-