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