English verb conjugation
SHOULD LENGTHEN

Regular verb: lengthen - lengthened - lengthened

Affirmation

Simple form	V-ing form
I'd lengthen you'd lengthen she'd lengthen we'd lengthen you'd lengthen they'd lengthen	I'd be lengthening you'd be lengthening she'd be lengthening we'd be lengthening you'd be lengthening they'd be lengthening
Perfect	V-ing perfect
I should've lengthened you should've lengthened she should've lengthened we should've lengthened you should've lengthened they should've lengthened	I should've been lengthening you should've been lengthening she should've been lengthening we should've been lengthening you should've been lengthening they should've been lengthening

Negation

Simple form	V-ing form
I shouldn't lengthen you shouldn't lengthen she shouldn't lengthen we shouldn't lengthen you shouldn't lengthen they shouldn't lengthen	I shouldn't be lengthening you shouldn't be lengthening she shouldn't be lengthening we shouldn't be lengthening you shouldn't be lengthening they shouldn't be lengthening
Perfect	V-ing perfect
I shouldn't have lengthened you shouldn't have lengthened she shouldn't have lengthened we shouldn't have lengthened you shouldn't have lengthened they shouldn't have lengthened	I shouldn't have been lengthening you shouldn't have been lengthening she shouldn't have been lengthening we shouldn't have been lengthening you shouldn't have been lengthening they shouldn't have been lengthening

Interrogative form

Simple form	V-ing form
should I lengthen? should you lengthen? should she lengthen? should we lengthen? should you lengthen? should they lengthen?	should I be lengthening? should you be lengthening? should she be lengthening? should we be lengthening? should you be lengthening? should they be lengthening?
Perfect	V-ing perfect
should I have lengthened? should you have lengthened? should she have lengthened? should we have lengthened? should you have lengthened? should they have lengthened?	should I have been lengthening? should you have been lengthening? should she have been lengthening? should we have been lengthening? should you have been lengthening? should they have been lengthening?

Interro-negative form

Simple form	V-ing form
shouldn't I lengthen? shouldn't you lengthen? shouldn't she lengthen? shouldn't we lengthen? shouldn't you lengthen? shouldn't they lengthen?	shouldn't I be lengthening? shouldn't you be lengthening? shouldn't she be lengthening? shouldn't we be lengthening? shouldn't you be lengthening? shouldn't they be lengthening?
Perfect	V-ing perfect
shouldn't I have lengthened? shouldn't you have lengthened? shouldn't she have lengthened? shouldn't we have lengthened? shouldn't you have lengthened? shouldn't they have lengthened?	shouldn't I have been lengthening? shouldn't you have been lengthening? shouldn't she have been lengthening? shouldn't we have been lengthening? shouldn't you have been lengthening? shouldn't they have been lengthening?