must foul
Regular verb: foul - fouled- fouled

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I must foul
you must foul
she must foul
we must foul
you must foul
they must foul 	I must be fouling
you must be fouling
she must be fouling
we must be fouling
you must be fouling
they must be fouling	I must have fouled
you must have fouled
she must have fouled
we must have fouled
you must have fouled
they must have fouled	I must have been fouling
you must have been fouling
she must have been fouling
we must have been fouling
you must have been fouling
they must have been fouling	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I mustn't foul
you mustn't foul
she mustn't foul
we mustn't foul
you mustn't foul
they mustn't foul 	I mustn't be fouling
you mustn't be fouling
she mustn't be fouling
we mustn't be fouling
you mustn't be fouling
they mustn't be fouling	I mustn't have fouled
you mustn't have fouled
she mustn't have fouled
we mustn't have fouled
you mustn't have fouled
they mustn't have fouled	I mustn't have been fouling
you mustn't have been fouling
she mustn't have been fouling
we mustn't have been fouling
you mustn't have been fouling
they mustn't have been fouling	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
must I foul?
must you foul?
must she foul?
must we foul?
must you foul?
must they foul? 	must I be fouling?
must you be fouling?
must she be fouling?
must we be fouling?
must you be fouling?
must they be fouling? 	must I have fouled?
must you have fouled?
must she have fouled?
must we have fouled?
must you have fouled?
must they have fouled? 	must I have been fouling?
must you have been fouling?
must she have been fouling?
must we have been fouling?
must you have been fouling?
must they have been fouling? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
mustn't I foul?
mustn't you foul?
mustn't she foul?
mustn't we foul?
mustn't you foul?
mustn't they foul? 	mustn't I be fouling?
mustn't you be fouling?
mustn't she be fouling?
mustn't we be fouling?
mustn't you be fouling?
mustn't they be fouling? 	mustn't I have fouled?
mustn't you have fouled?
mustn't she have fouled?
mustn't we have fouled?
mustn't you have fouled?
mustn't they have fouled? 	mustn't I have been fouling?
mustn't you have been fouling?
mustn't she have been fouling?
mustn't we have been fouling?
mustn't you have been fouling?
mustn't they have been fouling?