English verb conjugation
MUST SURF

Regular verb: surf - surfed - surfed

Affirmation

Simple form	V-ing form
I must surf you must surf she must surf we must surf you must surf they must surf	I must be surfing you must be surfing she must be surfing we must be surfing you must be surfing they must be surfing
Perfect	V-ing perfect
I must have surfed you must have surfed she must have surfed we must have surfed you must have surfed they must have surfed	I must have been surfing you must have been surfing she must have been surfing we must have been surfing you must have been surfing they must have been surfing

Negation

Simple form	V-ing form
I must not surf you must not surf she must not surf we must not surf you must not surf they must not surf	I must not be surfing you must not be surfing she must not be surfing we must not be surfing you must not be surfing they must not be surfing
Perfect	V-ing perfect
I must not have surfed you must not have surfed she must not have surfed we must not have surfed you must not have surfed they must not have surfed	I must not have been surfing you must not have been surfing she must not have been surfing we must not have been surfing you must not have been surfing they must not have been surfing

Interrogative form

Simple form	V-ing form
must I surf? must you surf? must she surf? must we surf? must you surf? must they surf?	must I be surfing? must you be surfing? must she be surfing? must we be surfing? must you be surfing? must they be surfing?
Perfect	V-ing perfect
must I have surfed? must you have surfed? must she have surfed? must we have surfed? must you have surfed? must they have surfed?	must I have been surfing? must you have been surfing? must she have been surfing? must we have been surfing? must you have been surfing? must they have been surfing?

Interro-negative form

Simple form	V-ing form
must I not surf? must you not surf? must she not surf? must we not surf? must you not surf? must they not surf?	must I not be surfing? must you not be surfing? must she not be surfing? must we not be surfing? must you not be surfing? must they not be surfing?
Perfect	V-ing perfect
must I not have surfed? must you not have surfed? must she not have surfed? must we not have surfed? must you not have surfed? must they not have surfed?	must I not have been surfing? must you not have been surfing? must she not have been surfing? must we not have been surfing? must you not have been surfing? must they not have been surfing?