must spare
Regular verb: spare - spared- spared

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I must spare
you must spare
he must spare
we must spare
you must spare
they must spare 	I must be sparing
you must be sparing
he must be sparing
we must be sparing
you must be sparing
they must be sparing	I must have spared
you must have spared
he must have spared
we must have spared
you must have spared
they must have spared	I must have been sparing
you must have been sparing
he must have been sparing
we must have been sparing
you must have been sparing
they must have been sparing	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I mustn't spare
you mustn't spare
he mustn't spare
we mustn't spare
you mustn't spare
they mustn't spare 	I mustn't be sparing
you mustn't be sparing
he mustn't be sparing
we mustn't be sparing
you mustn't be sparing
they mustn't be sparing	I mustn't have spared
you mustn't have spared
he mustn't have spared
we mustn't have spared
you mustn't have spared
they mustn't have spared	I mustn't have been sparing
you mustn't have been sparing
he mustn't have been sparing
we mustn't have been sparing
you mustn't have been sparing
they mustn't have been sparing	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
must I spare?
must you spare?
must he spare?
must we spare?
must you spare?
must they spare? 	must I be sparing?
must you be sparing?
must he be sparing?
must we be sparing?
must you be sparing?
must they be sparing? 	must I have spared?
must you have spared?
must he have spared?
must we have spared?
must you have spared?
must they have spared? 	must I have been sparing?
must you have been sparing?
must he have been sparing?
must we have been sparing?
must you have been sparing?
must they have been sparing? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
mustn't I spare?
mustn't you spare?
mustn't he spare?
mustn't we spare?
mustn't you spare?
mustn't they spare? 	mustn't I be sparing?
mustn't you be sparing?
mustn't he be sparing?
mustn't we be sparing?
mustn't you be sparing?
mustn't they be sparing? 	mustn't I have spared?
mustn't you have spared?
mustn't he have spared?
mustn't we have spared?
mustn't you have spared?
mustn't they have spared? 	mustn't I have been sparing?
mustn't you have been sparing?
mustn't he have been sparing?
mustn't we have been sparing?
mustn't you have been sparing?
mustn't they have been sparing?