I'd be investigating you'd be investigating he'd be investigating we'd be investigating you'd be investigating they'd be investigating
Perfect
I should've investigated you should've investigated he should've investigated we should've investigated you should've investigated they should've investigated
Perfect en V-ing
I should've been investigating you should've been investigating he should've been investigating we should've been investigating you should've been investigating they should've been investigating
Négation
Forme simple
I shouldn't investigate you shouldn't investigate he shouldn't investigate we shouldn't investigate you shouldn't investigate they shouldn't investigate
Forme en V-ing
I shouldn't be investigating you shouldn't be investigating he shouldn't be investigating we shouldn't be investigating you shouldn't be investigating they shouldn't be investigating
Perfect
I shouldn't have investigated you shouldn't have investigated he shouldn't have investigated we shouldn't have investigated you shouldn't have investigated they shouldn't have investigated
Perfect en V-ing
I shouldn't have been investigating you shouldn't have been investigating he shouldn't have been investigating we shouldn't have been investigating you shouldn't have been investigating they shouldn't have been investigating
Forme interrogative
Forme simple
should I investigate? should you investigate? should he investigate? should we investigate? should you investigate? should they investigate?
Forme en V-ing
should I be investigating? should you be investigating? should he be investigating? should we be investigating? should you be investigating? should they be investigating?
Perfect
should I have investigated? should you have investigated? should he have investigated? should we have investigated? should you have investigated? should they have investigated?
Perfect en V-ing
should I have been investigating? should you have been investigating? should he have been investigating? should we have been investigating? should you have been investigating? should they have been investigating?
Forme interro-négative
Forme simple
shouldn't I investigate? shouldn't you investigate? shouldn't he investigate? shouldn't we investigate? shouldn't you investigate? shouldn't they investigate?
Forme en V-ing
shouldn't I be investigating? shouldn't you be investigating? shouldn't he be investigating? shouldn't we be investigating? shouldn't you be investigating? shouldn't they be investigating?
Perfect
shouldn't I have investigated? shouldn't you have investigated? shouldn't he have investigated? shouldn't we have investigated? shouldn't you have investigated? shouldn't they have investigated?
Perfect en V-ing
shouldn't I have been investigating? shouldn't you have been investigating? shouldn't he have been investigating? shouldn't we have been investigating? shouldn't you have been investigating? shouldn't they have been investigating?