must thorn
Regular verb: thorn - thorned- thorned

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I must thorn
you must thorn
he must thorn
we must thorn
you must thorn
they must thorn 	I must be thorning
you must be thorning
he must be thorning
we must be thorning
you must be thorning
they must be thorning	I must have thorned
you must have thorned
he must have thorned
we must have thorned
you must have thorned
they must have thorned	I must have been thorning
you must have been thorning
he must have been thorning
we must have been thorning
you must have been thorning
they must have been thorning	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I must not thorn
you must not thorn
he must not thorn
we must not thorn
you must not thorn
they must not thorn 	I must not be thorning
you must not be thorning
he must not be thorning
we must not be thorning
you must not be thorning
they must not be thorning	I must not have thorned
you must not have thorned
he must not have thorned
we must not have thorned
you must not have thorned
they must not have thorned	I must not have been thorning
you must not have been thorning
he must not have been thorning
we must not have been thorning
you must not have been thorning
they must not have been thorning	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
must I thorn?
must you thorn?
must he thorn?
must we thorn?
must you thorn?
must they thorn? 	must I be thorning?
must you be thorning?
must he be thorning?
must we be thorning?
must you be thorning?
must they be thorning? 	must I have thorned?
must you have thorned?
must he have thorned?
must we have thorned?
must you have thorned?
must they have thorned? 	must I have been thorning?
must you have been thorning?
must he have been thorning?
must we have been thorning?
must you have been thorning?
must they have been thorning? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
must I not thorn?
must you not thorn?
must he not thorn?
must we not thorn?
must you not thorn?
must they not thorn? 	must I not be thorning?
must you not be thorning?
must he not be thorning?
must we not be thorning?
must you not be thorning?
must they not be thorning? 	must I not have thorned?
must you not have thorned?
must he not have thorned?
must we not have thorned?
must you not have thorned?
must they not have thorned? 	must I not have been thorning?
must you not have been thorning?
must he not have been thorning?
must we not have been thorning?
must you not have been thorning?
must they not have been thorning?