must yaw
Regular verb: yaw - yawed- yawed

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I must yaw
you must yaw
he must yaw
we must yaw
you must yaw
they must yaw 	I must be yawing
you must be yawing
he must be yawing
we must be yawing
you must be yawing
they must be yawing	I must have yawed
you must have yawed
he must have yawed
we must have yawed
you must have yawed
they must have yawed	I must have been yawing
you must have been yawing
he must have been yawing
we must have been yawing
you must have been yawing
they must have been yawing	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I mustn't yaw
you mustn't yaw
he mustn't yaw
we mustn't yaw
you mustn't yaw
they mustn't yaw 	I mustn't be yawing
you mustn't be yawing
he mustn't be yawing
we mustn't be yawing
you mustn't be yawing
they mustn't be yawing	I mustn't have yawed
you mustn't have yawed
he mustn't have yawed
we mustn't have yawed
you mustn't have yawed
they mustn't have yawed	I mustn't have been yawing
you mustn't have been yawing
he mustn't have been yawing
we mustn't have been yawing
you mustn't have been yawing
they mustn't have been yawing	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
must I yaw?
must you yaw?
must he yaw?
must we yaw?
must you yaw?
must they yaw? 	must I be yawing?
must you be yawing?
must he be yawing?
must we be yawing?
must you be yawing?
must they be yawing? 	must I have yawed?
must you have yawed?
must he have yawed?
must we have yawed?
must you have yawed?
must they have yawed? 	must I have been yawing?
must you have been yawing?
must he have been yawing?
must we have been yawing?
must you have been yawing?
must they have been yawing? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
mustn't I yaw?
mustn't you yaw?
mustn't he yaw?
mustn't we yaw?
mustn't you yaw?
mustn't they yaw? 	mustn't I be yawing?
mustn't you be yawing?
mustn't he be yawing?
mustn't we be yawing?
mustn't you be yawing?
mustn't they be yawing? 	mustn't I have yawed?
mustn't you have yawed?
mustn't he have yawed?
mustn't we have yawed?
mustn't you have yawed?
mustn't they have yawed? 	mustn't I have been yawing?
mustn't you have been yawing?
mustn't he have been yawing?
mustn't we have been yawing?
mustn't you have been yawing?
mustn't they have been yawing?