may blacken
Regular verb: blacken - blackened- blackened

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I may blacken
you may blacken
she may blacken
we may blacken
you may blacken
they may blacken 	I may be blackening
you may be blackening
she may be blackening
we may be blackening
you may be blackening
they may be blackening	I may have blackened
you may have blackened
she may have blackened
we may have blackened
you may have blackened
they may have blackened	I may have been blackening
you may have been blackening
she may have been blackening
we may have been blackening
you may have been blackening
they may have been blackening	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I mayn't blacken
you mayn't blacken
she mayn't blacken
we mayn't blacken
you mayn't blacken
they mayn't blacken 	I mayn't be blackening
you mayn't be blackening
she mayn't be blackening
we mayn't be blackening
you mayn't be blackening
they mayn't be blackening	I mayn't have blackened
you mayn't have blackened
she mayn't have blackened
we mayn't have blackened
you mayn't have blackened
they mayn't have blackened	I mayn't have been blackening
you mayn't have been blackening
she mayn't have been blackening
we mayn't have been blackening
you mayn't have been blackening
they mayn't have been blackening	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
may I blacken?
may you blacken?
may she blacken?
may we blacken?
may you blacken?
may they blacken? 	may I be blackening?
may you be blackening?
may she be blackening?
may we be blackening?
may you be blackening?
may they be blackening? 	may I have blackened?
may you have blackened?
may she have blackened?
may we have blackened?
may you have blackened?
may they have blackened? 	may I have been blackening?
may you have been blackening?
may she have been blackening?
may we have been blackening?
may you have been blackening?
may they have been blackening? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
mayn't I blacken?
mayn't you blacken?
mayn't she blacken?
mayn't we blacken?
mayn't you blacken?
mayn't they blacken? 	mayn't I be blackening?
mayn't you be blackening?
mayn't she be blackening?
mayn't we be blackening?
mayn't you be blackening?
mayn't they be blackening? 	mayn't I have blackened?
mayn't you have blackened?
mayn't she have blackened?
mayn't we have blackened?
mayn't you have blackened?
mayn't they have blackened? 	mayn't I have been blackening?
mayn't you have been blackening?
mayn't she have been blackening?
mayn't we have been blackening?
mayn't you have been blackening?
mayn't they have been blackening?