I'd be combining you'd be combining she'd be combining we'd be combining you'd be combining they'd be combining
Perfect
I should've combined you should've combined she should've combined we should've combined you should've combined they should've combined
V-ing perfect
I should've been combining you should've been combining she should've been combining we should've been combining you should've been combining they should've been combining
Negation
Simple form
I shouldn't combine you shouldn't combine she shouldn't combine we shouldn't combine you shouldn't combine they shouldn't combine
V-ing form
I shouldn't be combining you shouldn't be combining she shouldn't be combining we shouldn't be combining you shouldn't be combining they shouldn't be combining
Perfect
I shouldn't have combined you shouldn't have combined she shouldn't have combined we shouldn't have combined you shouldn't have combined they shouldn't have combined
V-ing perfect
I shouldn't have been combining you shouldn't have been combining she shouldn't have been combining we shouldn't have been combining you shouldn't have been combining they shouldn't have been combining
Interrogative form
Simple form
should I combine? should you combine? should she combine? should we combine? should you combine? should they combine?
V-ing form
should I be combining? should you be combining? should she be combining? should we be combining? should you be combining? should they be combining?
Perfect
should I have combined? should you have combined? should she have combined? should we have combined? should you have combined? should they have combined?
V-ing perfect
should I have been combining? should you have been combining? should she have been combining? should we have been combining? should you have been combining? should they have been combining?
Interro-negative form
Simple form
shouldn't I combine? shouldn't you combine? shouldn't she combine? shouldn't we combine? shouldn't you combine? shouldn't they combine?
V-ing form
shouldn't I be combining? shouldn't you be combining? shouldn't she be combining? shouldn't we be combining? shouldn't you be combining? shouldn't they be combining?
Perfect
shouldn't I have combined? shouldn't you have combined? shouldn't she have combined? shouldn't we have combined? shouldn't you have combined? shouldn't they have combined?
V-ing perfect
shouldn't I have been combining? shouldn't you have been combining? shouldn't she have been combining? shouldn't we have been combining? shouldn't you have been combining? shouldn't they have been combining?