English verb conjugation
COULD CERTIFICATE

Regular verb: certificate - certificated - certificated

Affirmation

Simple form	V-ing form
I could certificate you could certificate he could certificate we could certificate you could certificate they could certificate	I could be certificating you could be certificating he could be certificating we could be certificating you could be certificating they could be certificating
Perfect	V-ing perfect
I could have certificated you could have certificated he could have certificated we could have certificated you could have certificated they could have certificated	I could have been certificating you could have been certificating he could have been certificating we could have been certificating you could have been certificating they could have been certificating

Negation

Simple form	V-ing form
I could not certificate you could not certificate he could not certificate we could not certificate you could not certificate they could not certificate	I could not be certificating you could not be certificating he could not be certificating we could not be certificating you could not be certificating they could not be certificating
Perfect	V-ing perfect
I could not have certificated you could not have certificated he could not have certificated we could not have certificated you could not have certificated they could not have certificated	I could not have been certificating you could not have been certificating he could not have been certificating we could not have been certificating you could not have been certificating they could not have been certificating

Interrogative form

Simple form	V-ing form
could I certificate? could you certificate? could he certificate? could we certificate? could you certificate? could they certificate?	could I be certificating? could you be certificating? could he be certificating? could we be certificating? could you be certificating? could they be certificating?
Perfect	V-ing perfect
could I have certificated? could you have certificated? could he have certificated? could we have certificated? could you have certificated? could they have certificated?	could I have been certificating? could you have been certificating? could he have been certificating? could we have been certificating? could you have been certificating? could they have been certificating?

Interro-negative form

Simple form	V-ing form
could I not certificate? could you not certificate? could he not certificate? could we not certificate? could you not certificate? could they not certificate?	could I not be certificating? could you not be certificating? could he not be certificating? could we not be certificating? could you not be certificating? could they not be certificating?
Perfect	V-ing perfect
could I not have certificated? could you not have certificated? could he not have certificated? could we not have certificated? could you not have certificated? could they not have certificated?	could I not have been certificating? could you not have been certificating? could he not have been certificating? could we not have been certificating? could you not have been certificating? could they not have been certificating?