may slacken
Regular verb: slacken - slackened- slackened

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I may slacken
you may slacken
she may slacken
we may slacken
you may slacken
they may slacken 	I may be slackening
you may be slackening
she may be slackening
we may be slackening
you may be slackening
they may be slackening	I may have slackened
you may have slackened
she may have slackened
we may have slackened
you may have slackened
they may have slackened	I may have been slackening
you may have been slackening
she may have been slackening
we may have been slackening
you may have been slackening
they may have been slackening	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I mayn't slacken
you mayn't slacken
she mayn't slacken
we mayn't slacken
you mayn't slacken
they mayn't slacken 	I mayn't be slackening
you mayn't be slackening
she mayn't be slackening
we mayn't be slackening
you mayn't be slackening
they mayn't be slackening	I mayn't have slackened
you mayn't have slackened
she mayn't have slackened
we mayn't have slackened
you mayn't have slackened
they mayn't have slackened	I mayn't have been slackening
you mayn't have been slackening
she mayn't have been slackening
we mayn't have been slackening
you mayn't have been slackening
they mayn't have been slackening	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
may I slacken?
may you slacken?
may she slacken?
may we slacken?
may you slacken?
may they slacken? 	may I be slackening?
may you be slackening?
may she be slackening?
may we be slackening?
may you be slackening?
may they be slackening? 	may I have slackened?
may you have slackened?
may she have slackened?
may we have slackened?
may you have slackened?
may they have slackened? 	may I have been slackening?
may you have been slackening?
may she have been slackening?
may we have been slackening?
may you have been slackening?
may they have been slackening? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
mayn't I slacken?
mayn't you slacken?
mayn't she slacken?
mayn't we slacken?
mayn't you slacken?
mayn't they slacken? 	mayn't I be slackening?
mayn't you be slackening?
mayn't she be slackening?
mayn't we be slackening?
mayn't you be slackening?
mayn't they be slackening? 	mayn't I have slackened?
mayn't you have slackened?
mayn't she have slackened?
mayn't we have slackened?
mayn't you have slackened?
mayn't they have slackened? 	mayn't I have been slackening?
mayn't you have been slackening?
mayn't she have been slackening?
mayn't we have been slackening?
mayn't you have been slackening?
mayn't they have been slackening?