must fur
Regular verb: fur - furred- furred

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I must fur
you must fur
he must fur
we must fur
you must fur
they must fur 	I must be furring
you must be furring
he must be furring
we must be furring
you must be furring
they must be furring	I must have furred
you must have furred
he must have furred
we must have furred
you must have furred
they must have furred	I must have been furring
you must have been furring
he must have been furring
we must have been furring
you must have been furring
they must have been furring	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I must not fur
you must not fur
he must not fur
we must not fur
you must not fur
they must not fur 	I must not be furring
you must not be furring
he must not be furring
we must not be furring
you must not be furring
they must not be furring	I must not have furred
you must not have furred
he must not have furred
we must not have furred
you must not have furred
they must not have furred	I must not have been furring
you must not have been furring
he must not have been furring
we must not have been furring
you must not have been furring
they must not have been furring	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
must I fur?
must you fur?
must he fur?
must we fur?
must you fur?
must they fur? 	must I be furring?
must you be furring?
must he be furring?
must we be furring?
must you be furring?
must they be furring? 	must I have furred?
must you have furred?
must he have furred?
must we have furred?
must you have furred?
must they have furred? 	must I have been furring?
must you have been furring?
must he have been furring?
must we have been furring?
must you have been furring?
must they have been furring? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
must I not fur?
must you not fur?
must he not fur?
must we not fur?
must you not fur?
must they not fur? 	must I not be furring?
must you not be furring?
must he not be furring?
must we not be furring?
must you not be furring?
must they not be furring? 	must I not have furred?
must you not have furred?
must he not have furred?
must we not have furred?
must you not have furred?
must they not have furred? 	must I not have been furring?
must you not have been furring?
must he not have been furring?
must we not have been furring?
must you not have been furring?
must they not have been furring?