should tighten
Regular verb: tighten - tightened- tightened

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I should tighten
you should tighten
she should tighten
we should tighten
you should tighten
they should tighten 	I should be tightening
you should be tightening
she should be tightening
we should be tightening
you should be tightening
they should be tightening	I should have tightened
you should have tightened
she should have tightened
we should have tightened
you should have tightened
they should have tightened	I should have been tightening
you should have been tightening
she should have been tightening
we should have been tightening
you should have been tightening
they should have been tightening	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I should not tighten
you should not tighten
she should not tighten
we should not tighten
you should not tighten
they should not tighten 	I should not be tightening
you should not be tightening
she should not be tightening
we should not be tightening
you should not be tightening
they should not be tightening	I should not have tightened
you should not have tightened
she should not have tightened
we should not have tightened
you should not have tightened
they should not have tightened	I should not have been tightening
you should not have been tightening
she should not have been tightening
we should not have been tightening
you should not have been tightening
they should not have been tightening	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
should I tighten?
should you tighten?
should she tighten?
should we tighten?
should you tighten?
should they tighten? 	should I be tightening?
should you be tightening?
should she be tightening?
should we be tightening?
should you be tightening?
should they be tightening? 	should I have tightened?
should you have tightened?
should she have tightened?
should we have tightened?
should you have tightened?
should they have tightened? 	should I have been tightening?
should you have been tightening?
should she have been tightening?
should we have been tightening?
should you have been tightening?
should they have been tightening? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
should I not tighten?
should you not tighten?
should she not tighten?
should we not tighten?
should you not tighten?
should they not tighten? 	should I not be tightening?
should you not be tightening?
should she not be tightening?
should we not be tightening?
should you not be tightening?
should they not be tightening? 	should I not have tightened?
should you not have tightened?
should she not have tightened?
should we not have tightened?
should you not have tightened?
should they not have tightened? 	should I not have been tightening?
should you not have been tightening?
should she not have been tightening?
should we not have been tightening?
should you not have been tightening?
should they not have been tightening?