I'd be guarding you'd be guarding he'd be guarding we'd be guarding you'd be guarding they'd be guarding
Perfect
I should've guarded you should've guarded he should've guarded we should've guarded you should've guarded they should've guarded
V-ing perfect
I should've been guarding you should've been guarding he should've been guarding we should've been guarding you should've been guarding they should've been guarding
Negation
Simple form
I shouldn't guard you shouldn't guard he shouldn't guard we shouldn't guard you shouldn't guard they shouldn't guard
V-ing form
I shouldn't be guarding you shouldn't be guarding he shouldn't be guarding we shouldn't be guarding you shouldn't be guarding they shouldn't be guarding
Perfect
I shouldn't have guarded you shouldn't have guarded he shouldn't have guarded we shouldn't have guarded you shouldn't have guarded they shouldn't have guarded
V-ing perfect
I shouldn't have been guarding you shouldn't have been guarding he shouldn't have been guarding we shouldn't have been guarding you shouldn't have been guarding they shouldn't have been guarding
Interrogative form
Simple form
should I guard? should you guard? should he guard? should we guard? should you guard? should they guard?
V-ing form
should I be guarding? should you be guarding? should he be guarding? should we be guarding? should you be guarding? should they be guarding?
Perfect
should I have guarded? should you have guarded? should he have guarded? should we have guarded? should you have guarded? should they have guarded?
V-ing perfect
should I have been guarding? should you have been guarding? should he have been guarding? should we have been guarding? should you have been guarding? should they have been guarding?
Interro-negative form
Simple form
shouldn't I guard? shouldn't you guard? shouldn't he guard? shouldn't we guard? shouldn't you guard? shouldn't they guard?
V-ing form
shouldn't I be guarding? shouldn't you be guarding? shouldn't he be guarding? shouldn't we be guarding? shouldn't you be guarding? shouldn't they be guarding?
Perfect
shouldn't I have guarded? shouldn't you have guarded? shouldn't he have guarded? shouldn't we have guarded? shouldn't you have guarded? shouldn't they have guarded?
V-ing perfect
shouldn't I have been guarding? shouldn't you have been guarding? shouldn't he have been guarding? shouldn't we have been guarding? shouldn't you have been guarding? shouldn't they have been guarding?