English verb conjugation
COULD PENETRATE

Regular verb: penetrate - penetrated - penetrated

Affirmation

Simple form	V-ing form
I could penetrate you could penetrate he could penetrate we could penetrate you could penetrate they could penetrate	I could be penetrating you could be penetrating he could be penetrating we could be penetrating you could be penetrating they could be penetrating
Perfect	V-ing perfect
I could have penetrated you could have penetrated he could have penetrated we could have penetrated you could have penetrated they could have penetrated	I could have been penetrating you could have been penetrating he could have been penetrating we could have been penetrating you could have been penetrating they could have been penetrating

Negation

Simple form	V-ing form
I couldn't penetrate you couldn't penetrate he couldn't penetrate we couldn't penetrate you couldn't penetrate they couldn't penetrate	I couldn't be penetrating you couldn't be penetrating he couldn't be penetrating we couldn't be penetrating you couldn't be penetrating they couldn't be penetrating
Perfect	V-ing perfect
I couldn't have penetrated you couldn't have penetrated he couldn't have penetrated we couldn't have penetrated you couldn't have penetrated they couldn't have penetrated	I couldn't have been penetrating you couldn't have been penetrating he couldn't have been penetrating we couldn't have been penetrating you couldn't have been penetrating they couldn't have been penetrating

Interrogative form

Simple form	V-ing form
could I penetrate? could you penetrate? could he penetrate? could we penetrate? could you penetrate? could they penetrate?	could I be penetrating? could you be penetrating? could he be penetrating? could we be penetrating? could you be penetrating? could they be penetrating?
Perfect	V-ing perfect
could I have penetrated? could you have penetrated? could he have penetrated? could we have penetrated? could you have penetrated? could they have penetrated?	could I have been penetrating? could you have been penetrating? could he have been penetrating? could we have been penetrating? could you have been penetrating? could they have been penetrating?

Interro-negative form

Simple form	V-ing form
couldn't I penetrate? couldn't you penetrate? couldn't he penetrate? couldn't we penetrate? couldn't you penetrate? couldn't they penetrate?	couldn't I be penetrating? couldn't you be penetrating? couldn't he be penetrating? couldn't we be penetrating? couldn't you be penetrating? couldn't they be penetrating?
Perfect	V-ing perfect
couldn't I have penetrated? couldn't you have penetrated? couldn't he have penetrated? couldn't we have penetrated? couldn't you have penetrated? couldn't they have penetrated?	couldn't I have been penetrating? couldn't you have been penetrating? couldn't he have been penetrating? couldn't we have been penetrating? couldn't you have been penetrating? couldn't they have been penetrating?