shall slacken
Regular verb: slacken - slackened- slackened

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

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I shall not slacken
you shall not slacken
she shall not slacken
we shall not slacken
you shall not slacken
they shall not slacken 	I shall not be slackening
you shall not be slackening
she shall not be slackening
we shall not be slackening
you shall not be slackening
they shall not be slackening	I shall not have slackened
you shall not have slackened
she shall not have slackened
we shall not have slackened
you shall not have slackened
they shall not have slackened	I shall not have been slackening
you shall not have been slackening
she shall not have been slackening
we shall not have been slackening
you shall not have been slackening
they shall not have been slackening	

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

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