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