English verb conjugation MUST THUNDER
Regular verb: thunder - thundered - thundered
Affirmation
Simple form
--
it must thunder
-
-
-
V-ing form
--
it must be thundering
-
-
-
Perfect
--
it must have thundered
-
-
-
V-ing perfect
--
it must have been thundering
-
-
-
Negation
Simple form
--
it must not thunder
-
-
-
V-ing form
--
it must not be thundering
-
-
-
Perfect
--
it must not have thundered
-
-
-
V-ing perfect
--
it must not have been thundering
-
-
-
Interrogative form
Simple form
--
must it thunder?
-
-
-
V-ing form
--
must it be thundering?
-
-
-
Perfect
--
must it have thundered?
-
-
-
V-ing perfect
--
must it have been thundering?
-
-
-
Interro-negative form
Simple form
--
must it not thunder?
-
-
-
V-ing form
--
must it not be thundering?
-
-
-
Perfect
--
must it not have thundered?
-
-
-
V-ing perfect
--
must it not have been thundering?
-
-
-