must spay
Regular verb: spay - spayed- spayed

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I must spay
you must spay
he must spay
we must spay
you must spay
they must spay 	I must be spaying
you must be spaying
he must be spaying
we must be spaying
you must be spaying
they must be spaying	I must have spayed
you must have spayed
he must have spayed
we must have spayed
you must have spayed
they must have spayed	I must have been spaying
you must have been spaying
he must have been spaying
we must have been spaying
you must have been spaying
they must have been spaying	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I mustn't spay
you mustn't spay
he mustn't spay
we mustn't spay
you mustn't spay
they mustn't spay 	I mustn't be spaying
you mustn't be spaying
he mustn't be spaying
we mustn't be spaying
you mustn't be spaying
they mustn't be spaying	I mustn't have spayed
you mustn't have spayed
he mustn't have spayed
we mustn't have spayed
you mustn't have spayed
they mustn't have spayed	I mustn't have been spaying
you mustn't have been spaying
he mustn't have been spaying
we mustn't have been spaying
you mustn't have been spaying
they mustn't have been spaying	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
must I spay?
must you spay?
must he spay?
must we spay?
must you spay?
must they spay? 	must I be spaying?
must you be spaying?
must he be spaying?
must we be spaying?
must you be spaying?
must they be spaying? 	must I have spayed?
must you have spayed?
must he have spayed?
must we have spayed?
must you have spayed?
must they have spayed? 	must I have been spaying?
must you have been spaying?
must he have been spaying?
must we have been spaying?
must you have been spaying?
must they have been spaying? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
mustn't I spay?
mustn't you spay?
mustn't he spay?
mustn't we spay?
mustn't you spay?
mustn't they spay? 	mustn't I be spaying?
mustn't you be spaying?
mustn't he be spaying?
mustn't we be spaying?
mustn't you be spaying?
mustn't they be spaying? 	mustn't I have spayed?
mustn't you have spayed?
mustn't he have spayed?
mustn't we have spayed?
mustn't you have spayed?
mustn't they have spayed? 	mustn't I have been spaying?
mustn't you have been spaying?
mustn't he have been spaying?
mustn't we have been spaying?
mustn't you have been spaying?
mustn't they have been spaying?