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