English verb conjugation
MUST PURL

Regular verb: purl - purled - purled

Affirmation

Simple form	V-ing form
I must purl you must purl he must purl we must purl you must purl they must purl	I must be purling you must be purling he must be purling we must be purling you must be purling they must be purling
Perfect	V-ing perfect
I must have purled you must have purled he must have purled we must have purled you must have purled they must have purled	I must have been purling you must have been purling he must have been purling we must have been purling you must have been purling they must have been purling

Negation

Simple form	V-ing form
I must not purl you must not purl he must not purl we must not purl you must not purl they must not purl	I must not be purling you must not be purling he must not be purling we must not be purling you must not be purling they must not be purling
Perfect	V-ing perfect
I must not have purled you must not have purled he must not have purled we must not have purled you must not have purled they must not have purled	I must not have been purling you must not have been purling he must not have been purling we must not have been purling you must not have been purling they must not have been purling

Interrogative form

Simple form	V-ing form
must I purl? must you purl? must he purl? must we purl? must you purl? must they purl?	must I be purling? must you be purling? must he be purling? must we be purling? must you be purling? must they be purling?
Perfect	V-ing perfect
must I have purled? must you have purled? must he have purled? must we have purled? must you have purled? must they have purled?	must I have been purling? must you have been purling? must he have been purling? must we have been purling? must you have been purling? must they have been purling?

Interro-negative form

Simple form	V-ing form
must I not purl? must you not purl? must he not purl? must we not purl? must you not purl? must they not purl?	must I not be purling? must you not be purling? must he not be purling? must we not be purling? must you not be purling? must they not be purling?
Perfect	V-ing perfect
must I not have purled? must you not have purled? must he not have purled? must we not have purled? must you not have purled? must they not have purled?	must I not have been purling? must you not have been purling? must he not have been purling? must we not have been purling? must you not have been purling? must they not have been purling?