English verb conjugation
SHOULD INTERVENE

Regular verb: intervene - intervened - intervened

Affirmation

Simple form	V-ing form
I'd intervene you'd intervene he'd intervene we'd intervene you'd intervene they'd intervene	I'd be intervening you'd be intervening he'd be intervening we'd be intervening you'd be intervening they'd be intervening
Perfect	V-ing perfect
I should've intervened you should've intervened he should've intervened we should've intervened you should've intervened they should've intervened	I should've been intervening you should've been intervening he should've been intervening we should've been intervening you should've been intervening they should've been intervening

Negation

Simple form	V-ing form
I shouldn't intervene you shouldn't intervene he shouldn't intervene we shouldn't intervene you shouldn't intervene they shouldn't intervene	I shouldn't be intervening you shouldn't be intervening he shouldn't be intervening we shouldn't be intervening you shouldn't be intervening they shouldn't be intervening
Perfect	V-ing perfect
I shouldn't have intervened you shouldn't have intervened he shouldn't have intervened we shouldn't have intervened you shouldn't have intervened they shouldn't have intervened	I shouldn't have been intervening you shouldn't have been intervening he shouldn't have been intervening we shouldn't have been intervening you shouldn't have been intervening they shouldn't have been intervening

Interrogative form

Simple form	V-ing form
should I intervene? should you intervene? should he intervene? should we intervene? should you intervene? should they intervene?	should I be intervening? should you be intervening? should he be intervening? should we be intervening? should you be intervening? should they be intervening?
Perfect	V-ing perfect
should I have intervened? should you have intervened? should he have intervened? should we have intervened? should you have intervened? should they have intervened?	should I have been intervening? should you have been intervening? should he have been intervening? should we have been intervening? should you have been intervening? should they have been intervening?

Interro-negative form

Simple form	V-ing form
shouldn't I intervene? shouldn't you intervene? shouldn't he intervene? shouldn't we intervene? shouldn't you intervene? shouldn't they intervene?	shouldn't I be intervening? shouldn't you be intervening? shouldn't he be intervening? shouldn't we be intervening? shouldn't you be intervening? shouldn't they be intervening?
Perfect	V-ing perfect
shouldn't I have intervened? shouldn't you have intervened? shouldn't he have intervened? shouldn't we have intervened? shouldn't you have intervened? shouldn't they have intervened?	shouldn't I have been intervening? shouldn't you have been intervening? shouldn't he have been intervening? shouldn't we have been intervening? shouldn't you have been intervening? shouldn't they have been intervening?