may catalyse
Regular verb: catalyse - catalysed- catalysed

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I may catalyse
you may catalyse
she may catalyse
we may catalyse
you may catalyse
they may catalyse 	I may be catalysing
you may be catalysing
she may be catalysing
we may be catalysing
you may be catalysing
they may be catalysing	I may have catalysed
you may have catalysed
she may have catalysed
we may have catalysed
you may have catalysed
they may have catalysed	I may have been catalysing
you may have been catalysing
she may have been catalysing
we may have been catalysing
you may have been catalysing
they may have been catalysing	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I mayn't catalyse
you mayn't catalyse
she mayn't catalyse
we mayn't catalyse
you mayn't catalyse
they mayn't catalyse 	I mayn't be catalysing
you mayn't be catalysing
she mayn't be catalysing
we mayn't be catalysing
you mayn't be catalysing
they mayn't be catalysing	I mayn't have catalysed
you mayn't have catalysed
she mayn't have catalysed
we mayn't have catalysed
you mayn't have catalysed
they mayn't have catalysed	I mayn't have been catalysing
you mayn't have been catalysing
she mayn't have been catalysing
we mayn't have been catalysing
you mayn't have been catalysing
they mayn't have been catalysing	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
may I catalyse?
may you catalyse?
may she catalyse?
may we catalyse?
may you catalyse?
may they catalyse? 	may I be catalysing?
may you be catalysing?
may she be catalysing?
may we be catalysing?
may you be catalysing?
may they be catalysing? 	may I have catalysed?
may you have catalysed?
may she have catalysed?
may we have catalysed?
may you have catalysed?
may they have catalysed? 	may I have been catalysing?
may you have been catalysing?
may she have been catalysing?
may we have been catalysing?
may you have been catalysing?
may they have been catalysing? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
mayn't I catalyse?
mayn't you catalyse?
mayn't she catalyse?
mayn't we catalyse?
mayn't you catalyse?
mayn't they catalyse? 	mayn't I be catalysing?
mayn't you be catalysing?
mayn't she be catalysing?
mayn't we be catalysing?
mayn't you be catalysing?
mayn't they be catalysing? 	mayn't I have catalysed?
mayn't you have catalysed?
mayn't she have catalysed?
mayn't we have catalysed?
mayn't you have catalysed?
mayn't they have catalysed? 	mayn't I have been catalysing?
mayn't you have been catalysing?
mayn't she have been catalysing?
mayn't we have been catalysing?
mayn't you have been catalysing?
mayn't they have been catalysing?