must ad-lib
Regular verb: ad-lib - ad-libed- ad-libed

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I must ad-lib
you must ad-lib
he must ad-lib
we must ad-lib
you must ad-lib
they must ad-lib 	I must be ad-libing
you must be ad-libing
he must be ad-libing
we must be ad-libing
you must be ad-libing
they must be ad-libing	I must have ad-libed
you must have ad-libed
he must have ad-libed
we must have ad-libed
you must have ad-libed
they must have ad-libed	I must have been ad-libing
you must have been ad-libing
he must have been ad-libing
we must have been ad-libing
you must have been ad-libing
they must have been ad-libing	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I must not ad-lib
you must not ad-lib
he must not ad-lib
we must not ad-lib
you must not ad-lib
they must not ad-lib 	I must not be ad-libing
you must not be ad-libing
he must not be ad-libing
we must not be ad-libing
you must not be ad-libing
they must not be ad-libing	I must not have ad-libed
you must not have ad-libed
he must not have ad-libed
we must not have ad-libed
you must not have ad-libed
they must not have ad-libed	I must not have been ad-libing
you must not have been ad-libing
he must not have been ad-libing
we must not have been ad-libing
you must not have been ad-libing
they must not have been ad-libing	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
must I ad-lib?
must you ad-lib?
must he ad-lib?
must we ad-lib?
must you ad-lib?
must they ad-lib? 	must I be ad-libing?
must you be ad-libing?
must he be ad-libing?
must we be ad-libing?
must you be ad-libing?
must they be ad-libing? 	must I have ad-libed?
must you have ad-libed?
must he have ad-libed?
must we have ad-libed?
must you have ad-libed?
must they have ad-libed? 	must I have been ad-libing?
must you have been ad-libing?
must he have been ad-libing?
must we have been ad-libing?
must you have been ad-libing?
must they have been ad-libing? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
must I not ad-lib?
must you not ad-lib?
must he not ad-lib?
must we not ad-lib?
must you not ad-lib?
must they not ad-lib? 	must I not be ad-libing?
must you not be ad-libing?
must he not be ad-libing?
must we not be ad-libing?
must you not be ad-libing?
must they not be ad-libing? 	must I not have ad-libed?
must you not have ad-libed?
must he not have ad-libed?
must we not have ad-libed?
must you not have ad-libed?
must they not have ad-libed? 	must I not have been ad-libing?
must you not have been ad-libing?
must he not have been ad-libing?
must we not have been ad-libing?
must you not have been ad-libing?
must they not have been ad-libing?