may darken
Regular verb: darken - darkened- darkened

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I may darken
you may darken
he may darken
we may darken
you may darken
they may darken 	I may be darkening
you may be darkening
he may be darkening
we may be darkening
you may be darkening
they may be darkening	I may have darkened
you may have darkened
he may have darkened
we may have darkened
you may have darkened
they may have darkened	I may have been darkening
you may have been darkening
he may have been darkening
we may have been darkening
you may have been darkening
they may have been darkening	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I mayn't darken
you mayn't darken
he mayn't darken
we mayn't darken
you mayn't darken
they mayn't darken 	I mayn't be darkening
you mayn't be darkening
he mayn't be darkening
we mayn't be darkening
you mayn't be darkening
they mayn't be darkening	I mayn't have darkened
you mayn't have darkened
he mayn't have darkened
we mayn't have darkened
you mayn't have darkened
they mayn't have darkened	I mayn't have been darkening
you mayn't have been darkening
he mayn't have been darkening
we mayn't have been darkening
you mayn't have been darkening
they mayn't have been darkening	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
may I darken?
may you darken?
may he darken?
may we darken?
may you darken?
may they darken? 	may I be darkening?
may you be darkening?
may he be darkening?
may we be darkening?
may you be darkening?
may they be darkening? 	may I have darkened?
may you have darkened?
may he have darkened?
may we have darkened?
may you have darkened?
may they have darkened? 	may I have been darkening?
may you have been darkening?
may he have been darkening?
may we have been darkening?
may you have been darkening?
may they have been darkening? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
mayn't I darken?
mayn't you darken?
mayn't he darken?
mayn't we darken?
mayn't you darken?
mayn't they darken? 	mayn't I be darkening?
mayn't you be darkening?
mayn't he be darkening?
mayn't we be darkening?
mayn't you be darkening?
mayn't they be darkening? 	mayn't I have darkened?
mayn't you have darkened?
mayn't he have darkened?
mayn't we have darkened?
mayn't you have darkened?
mayn't they have darkened? 	mayn't I have been darkening?
mayn't you have been darkening?
mayn't he have been darkening?
mayn't we have been darkening?
mayn't you have been darkening?
mayn't they have been darkening?