must twin
Regular verb: twin - twinned- twinned

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I must twin
you must twin
he must twin
we must twin
you must twin
they must twin 	I must be twinning
you must be twinning
he must be twinning
we must be twinning
you must be twinning
they must be twinning	I must have twinned
you must have twinned
he must have twinned
we must have twinned
you must have twinned
they must have twinned	I must have been twinning
you must have been twinning
he must have been twinning
we must have been twinning
you must have been twinning
they must have been twinning	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I must not twin
you must not twin
he must not twin
we must not twin
you must not twin
they must not twin 	I must not be twinning
you must not be twinning
he must not be twinning
we must not be twinning
you must not be twinning
they must not be twinning	I must not have twinned
you must not have twinned
he must not have twinned
we must not have twinned
you must not have twinned
they must not have twinned	I must not have been twinning
you must not have been twinning
he must not have been twinning
we must not have been twinning
you must not have been twinning
they must not have been twinning	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
must I twin?
must you twin?
must he twin?
must we twin?
must you twin?
must they twin? 	must I be twinning?
must you be twinning?
must he be twinning?
must we be twinning?
must you be twinning?
must they be twinning? 	must I have twinned?
must you have twinned?
must he have twinned?
must we have twinned?
must you have twinned?
must they have twinned? 	must I have been twinning?
must you have been twinning?
must he have been twinning?
must we have been twinning?
must you have been twinning?
must they have been twinning? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
must I not twin?
must you not twin?
must he not twin?
must we not twin?
must you not twin?
must they not twin? 	must I not be twinning?
must you not be twinning?
must he not be twinning?
must we not be twinning?
must you not be twinning?
must they not be twinning? 	must I not have twinned?
must you not have twinned?
must he not have twinned?
must we not have twinned?
must you not have twinned?
must they not have twinned? 	must I not have been twinning?
must you not have been twinning?
must he not have been twinning?
must we not have been twinning?
must you not have been twinning?
must they not have been twinning?