must glass
Regular verb: glass - glassed- glassed

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I must glass
you must glass
he must glass
we must glass
you must glass
they must glass 	I must be glassing
you must be glassing
he must be glassing
we must be glassing
you must be glassing
they must be glassing	I must have glassed
you must have glassed
he must have glassed
we must have glassed
you must have glassed
they must have glassed	I must have been glassing
you must have been glassing
he must have been glassing
we must have been glassing
you must have been glassing
they must have been glassing	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I mustn't glass
you mustn't glass
he mustn't glass
we mustn't glass
you mustn't glass
they mustn't glass 	I mustn't be glassing
you mustn't be glassing
he mustn't be glassing
we mustn't be glassing
you mustn't be glassing
they mustn't be glassing	I mustn't have glassed
you mustn't have glassed
he mustn't have glassed
we mustn't have glassed
you mustn't have glassed
they mustn't have glassed	I mustn't have been glassing
you mustn't have been glassing
he mustn't have been glassing
we mustn't have been glassing
you mustn't have been glassing
they mustn't have been glassing	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
must I glass?
must you glass?
must he glass?
must we glass?
must you glass?
must they glass? 	must I be glassing?
must you be glassing?
must he be glassing?
must we be glassing?
must you be glassing?
must they be glassing? 	must I have glassed?
must you have glassed?
must he have glassed?
must we have glassed?
must you have glassed?
must they have glassed? 	must I have been glassing?
must you have been glassing?
must he have been glassing?
must we have been glassing?
must you have been glassing?
must they have been glassing? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
mustn't I glass?
mustn't you glass?
mustn't he glass?
mustn't we glass?
mustn't you glass?
mustn't they glass? 	mustn't I be glassing?
mustn't you be glassing?
mustn't he be glassing?
mustn't we be glassing?
mustn't you be glassing?
mustn't they be glassing? 	mustn't I have glassed?
mustn't you have glassed?
mustn't he have glassed?
mustn't we have glassed?
mustn't you have glassed?
mustn't they have glassed? 	mustn't I have been glassing?
mustn't you have been glassing?
mustn't he have been glassing?
mustn't we have been glassing?
mustn't you have been glassing?
mustn't they have been glassing?