must devise
Regular verb: devise - devised- devised

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I must devise
you must devise
she must devise
we must devise
you must devise
they must devise 	I must be devising
you must be devising
she must be devising
we must be devising
you must be devising
they must be devising	I must have devised
you must have devised
she must have devised
we must have devised
you must have devised
they must have devised	I must have been devising
you must have been devising
she must have been devising
we must have been devising
you must have been devising
they must have been devising	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I mustn't devise
you mustn't devise
she mustn't devise
we mustn't devise
you mustn't devise
they mustn't devise 	I mustn't be devising
you mustn't be devising
she mustn't be devising
we mustn't be devising
you mustn't be devising
they mustn't be devising	I mustn't have devised
you mustn't have devised
she mustn't have devised
we mustn't have devised
you mustn't have devised
they mustn't have devised	I mustn't have been devising
you mustn't have been devising
she mustn't have been devising
we mustn't have been devising
you mustn't have been devising
they mustn't have been devising	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
must I devise?
must you devise?
must she devise?
must we devise?
must you devise?
must they devise? 	must I be devising?
must you be devising?
must she be devising?
must we be devising?
must you be devising?
must they be devising? 	must I have devised?
must you have devised?
must she have devised?
must we have devised?
must you have devised?
must they have devised? 	must I have been devising?
must you have been devising?
must she have been devising?
must we have been devising?
must you have been devising?
must they have been devising? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
mustn't I devise?
mustn't you devise?
mustn't she devise?
mustn't we devise?
mustn't you devise?
mustn't they devise? 	mustn't I be devising?
mustn't you be devising?
mustn't she be devising?
mustn't we be devising?
mustn't you be devising?
mustn't they be devising? 	mustn't I have devised?
mustn't you have devised?
mustn't she have devised?
mustn't we have devised?
mustn't you have devised?
mustn't they have devised? 	mustn't I have been devising?
mustn't you have been devising?
mustn't she have been devising?
mustn't we have been devising?
mustn't you have been devising?
mustn't they have been devising?