must fuse
Regular verb: fuse - fused- fused

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I must fuse
you must fuse
she must fuse
we must fuse
you must fuse
they must fuse 	I must be fusing
you must be fusing
she must be fusing
we must be fusing
you must be fusing
they must be fusing	I must have fused
you must have fused
she must have fused
we must have fused
you must have fused
they must have fused	I must have been fusing
you must have been fusing
she must have been fusing
we must have been fusing
you must have been fusing
they must have been fusing	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I mustn't fuse
you mustn't fuse
she mustn't fuse
we mustn't fuse
you mustn't fuse
they mustn't fuse 	I mustn't be fusing
you mustn't be fusing
she mustn't be fusing
we mustn't be fusing
you mustn't be fusing
they mustn't be fusing	I mustn't have fused
you mustn't have fused
she mustn't have fused
we mustn't have fused
you mustn't have fused
they mustn't have fused	I mustn't have been fusing
you mustn't have been fusing
she mustn't have been fusing
we mustn't have been fusing
you mustn't have been fusing
they mustn't have been fusing	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
must I fuse?
must you fuse?
must she fuse?
must we fuse?
must you fuse?
must they fuse? 	must I be fusing?
must you be fusing?
must she be fusing?
must we be fusing?
must you be fusing?
must they be fusing? 	must I have fused?
must you have fused?
must she have fused?
must we have fused?
must you have fused?
must they have fused? 	must I have been fusing?
must you have been fusing?
must she have been fusing?
must we have been fusing?
must you have been fusing?
must they have been fusing? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
mustn't I fuse?
mustn't you fuse?
mustn't she fuse?
mustn't we fuse?
mustn't you fuse?
mustn't they fuse? 	mustn't I be fusing?
mustn't you be fusing?
mustn't she be fusing?
mustn't we be fusing?
mustn't you be fusing?
mustn't they be fusing? 	mustn't I have fused?
mustn't you have fused?
mustn't she have fused?
mustn't we have fused?
mustn't you have fused?
mustn't they have fused? 	mustn't I have been fusing?
mustn't you have been fusing?
mustn't she have been fusing?
mustn't we have been fusing?
mustn't you have been fusing?
mustn't they have been fusing?