must focus
Regular verb: focus - focused- focused

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I must focus
you must focus
she must focus
we must focus
you must focus
they must focus 	I must be focusing
you must be focusing
she must be focusing
we must be focusing
you must be focusing
they must be focusing	I must have focused
you must have focused
she must have focused
we must have focused
you must have focused
they must have focused	I must have been focusing
you must have been focusing
she must have been focusing
we must have been focusing
you must have been focusing
they must have been focusing	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I mustn't focus
you mustn't focus
she mustn't focus
we mustn't focus
you mustn't focus
they mustn't focus 	I mustn't be focusing
you mustn't be focusing
she mustn't be focusing
we mustn't be focusing
you mustn't be focusing
they mustn't be focusing	I mustn't have focused
you mustn't have focused
she mustn't have focused
we mustn't have focused
you mustn't have focused
they mustn't have focused	I mustn't have been focusing
you mustn't have been focusing
she mustn't have been focusing
we mustn't have been focusing
you mustn't have been focusing
they mustn't have been focusing	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
must I focus?
must you focus?
must she focus?
must we focus?
must you focus?
must they focus? 	must I be focusing?
must you be focusing?
must she be focusing?
must we be focusing?
must you be focusing?
must they be focusing? 	must I have focused?
must you have focused?
must she have focused?
must we have focused?
must you have focused?
must they have focused? 	must I have been focusing?
must you have been focusing?
must she have been focusing?
must we have been focusing?
must you have been focusing?
must they have been focusing? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
mustn't I focus?
mustn't you focus?
mustn't she focus?
mustn't we focus?
mustn't you focus?
mustn't they focus? 	mustn't I be focusing?
mustn't you be focusing?
mustn't she be focusing?
mustn't we be focusing?
mustn't you be focusing?
mustn't they be focusing? 	mustn't I have focused?
mustn't you have focused?
mustn't she have focused?
mustn't we have focused?
mustn't you have focused?
mustn't they have focused? 	mustn't I have been focusing?
mustn't you have been focusing?
mustn't she have been focusing?
mustn't we have been focusing?
mustn't you have been focusing?
mustn't they have been focusing?