English verb conjugation
COULD OPERATE

Regular verb: operate - operated - operated

Affirmation

Simple form	V-ing form
I could operate you could operate she could operate we could operate you could operate they could operate	I could be operating you could be operating she could be operating we could be operating you could be operating they could be operating
Perfect	V-ing perfect
I could have operated you could have operated she could have operated we could have operated you could have operated they could have operated	I could have been operating you could have been operating she could have been operating we could have been operating you could have been operating they could have been operating

Negation

Simple form	V-ing form
I couldn't operate you couldn't operate she couldn't operate we couldn't operate you couldn't operate they couldn't operate	I couldn't be operating you couldn't be operating she couldn't be operating we couldn't be operating you couldn't be operating they couldn't be operating
Perfect	V-ing perfect
I couldn't have operated you couldn't have operated she couldn't have operated we couldn't have operated you couldn't have operated they couldn't have operated	I couldn't have been operating you couldn't have been operating she couldn't have been operating we couldn't have been operating you couldn't have been operating they couldn't have been operating

Interrogative form

Simple form	V-ing form
could I operate? could you operate? could she operate? could we operate? could you operate? could they operate?	could I be operating? could you be operating? could she be operating? could we be operating? could you be operating? could they be operating?
Perfect	V-ing perfect
could I have operated? could you have operated? could she have operated? could we have operated? could you have operated? could they have operated?	could I have been operating? could you have been operating? could she have been operating? could we have been operating? could you have been operating? could they have been operating?

Interro-negative form

Simple form	V-ing form
couldn't I operate? couldn't you operate? couldn't she operate? couldn't we operate? couldn't you operate? couldn't they operate?	couldn't I be operating? couldn't you be operating? couldn't she be operating? couldn't we be operating? couldn't you be operating? couldn't they be operating?
Perfect	V-ing perfect
couldn't I have operated? couldn't you have operated? couldn't she have operated? couldn't we have operated? couldn't you have operated? couldn't they have operated?	couldn't I have been operating? couldn't you have been operating? couldn't she have been operating? couldn't we have been operating? couldn't you have been operating? couldn't they have been operating?