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