must spur
Regular verb: spur - spurred- spurred

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I must spur
you must spur
he must spur
we must spur
you must spur
they must spur 	I must be spurring
you must be spurring
he must be spurring
we must be spurring
you must be spurring
they must be spurring	I must have spurred
you must have spurred
he must have spurred
we must have spurred
you must have spurred
they must have spurred	I must have been spurring
you must have been spurring
he must have been spurring
we must have been spurring
you must have been spurring
they must have been spurring	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I mustn't spur
you mustn't spur
he mustn't spur
we mustn't spur
you mustn't spur
they mustn't spur 	I mustn't be spurring
you mustn't be spurring
he mustn't be spurring
we mustn't be spurring
you mustn't be spurring
they mustn't be spurring	I mustn't have spurred
you mustn't have spurred
he mustn't have spurred
we mustn't have spurred
you mustn't have spurred
they mustn't have spurred	I mustn't have been spurring
you mustn't have been spurring
he mustn't have been spurring
we mustn't have been spurring
you mustn't have been spurring
they mustn't have been spurring	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
must I spur?
must you spur?
must he spur?
must we spur?
must you spur?
must they spur? 	must I be spurring?
must you be spurring?
must he be spurring?
must we be spurring?
must you be spurring?
must they be spurring? 	must I have spurred?
must you have spurred?
must he have spurred?
must we have spurred?
must you have spurred?
must they have spurred? 	must I have been spurring?
must you have been spurring?
must he have been spurring?
must we have been spurring?
must you have been spurring?
must they have been spurring? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
mustn't I spur?
mustn't you spur?
mustn't he spur?
mustn't we spur?
mustn't you spur?
mustn't they spur? 	mustn't I be spurring?
mustn't you be spurring?
mustn't he be spurring?
mustn't we be spurring?
mustn't you be spurring?
mustn't they be spurring? 	mustn't I have spurred?
mustn't you have spurred?
mustn't he have spurred?
mustn't we have spurred?
mustn't you have spurred?
mustn't they have spurred? 	mustn't I have been spurring?
mustn't you have been spurring?
mustn't he have been spurring?
mustn't we have been spurring?
mustn't you have been spurring?
mustn't they have been spurring?