English verb conjugation
SHOULD PURCHASE

Regular verb: purchase - purchased - purchased

Affirmation

Simple form	V-ing form
I'd purchase you'd purchase he'd purchase we'd purchase you'd purchase they'd purchase	I'd be purchasing you'd be purchasing he'd be purchasing we'd be purchasing you'd be purchasing they'd be purchasing
Perfect	V-ing perfect
I should've purchased you should've purchased he should've purchased we should've purchased you should've purchased they should've purchased	I should've been purchasing you should've been purchasing he should've been purchasing we should've been purchasing you should've been purchasing they should've been purchasing

Negation

Simple form	V-ing form
I shouldn't purchase you shouldn't purchase he shouldn't purchase we shouldn't purchase you shouldn't purchase they shouldn't purchase	I shouldn't be purchasing you shouldn't be purchasing he shouldn't be purchasing we shouldn't be purchasing you shouldn't be purchasing they shouldn't be purchasing
Perfect	V-ing perfect
I shouldn't have purchased you shouldn't have purchased he shouldn't have purchased we shouldn't have purchased you shouldn't have purchased they shouldn't have purchased	I shouldn't have been purchasing you shouldn't have been purchasing he shouldn't have been purchasing we shouldn't have been purchasing you shouldn't have been purchasing they shouldn't have been purchasing

Interrogative form

Simple form	V-ing form
should I purchase? should you purchase? should he purchase? should we purchase? should you purchase? should they purchase?	should I be purchasing? should you be purchasing? should he be purchasing? should we be purchasing? should you be purchasing? should they be purchasing?
Perfect	V-ing perfect
should I have purchased? should you have purchased? should he have purchased? should we have purchased? should you have purchased? should they have purchased?	should I have been purchasing? should you have been purchasing? should he have been purchasing? should we have been purchasing? should you have been purchasing? should they have been purchasing?

Interro-negative form

Simple form	V-ing form
shouldn't I purchase? shouldn't you purchase? shouldn't he purchase? shouldn't we purchase? shouldn't you purchase? shouldn't they purchase?	shouldn't I be purchasing? shouldn't you be purchasing? shouldn't he be purchasing? shouldn't we be purchasing? shouldn't you be purchasing? shouldn't they be purchasing?
Perfect	V-ing perfect
shouldn't I have purchased? shouldn't you have purchased? shouldn't he have purchased? shouldn't we have purchased? shouldn't you have purchased? shouldn't they have purchased?	shouldn't I have been purchasing? shouldn't you have been purchasing? shouldn't he have been purchasing? shouldn't we have been purchasing? shouldn't you have been purchasing? shouldn't they have been purchasing?