English verb conjugation
COULD UNDERTAIN

Regular verb: undertain - undertained - undertained

Affirmation

Simple form	V-ing form
I could undertain you could undertain he could undertain we could undertain you could undertain they could undertain	I could be undertaining you could be undertaining he could be undertaining we could be undertaining you could be undertaining they could be undertaining
Perfect	V-ing perfect
I could have undertained you could have undertained he could have undertained we could have undertained you could have undertained they could have undertained	I could have been undertaining you could have been undertaining he could have been undertaining we could have been undertaining you could have been undertaining they could have been undertaining

Negation

Simple form	V-ing form
I could not undertain you could not undertain he could not undertain we could not undertain you could not undertain they could not undertain	I could not be undertaining you could not be undertaining he could not be undertaining we could not be undertaining you could not be undertaining they could not be undertaining
Perfect	V-ing perfect
I could not have undertained you could not have undertained he could not have undertained we could not have undertained you could not have undertained they could not have undertained	I could not have been undertaining you could not have been undertaining he could not have been undertaining we could not have been undertaining you could not have been undertaining they could not have been undertaining

Interrogative form

Simple form	V-ing form
could I undertain? could you undertain? could he undertain? could we undertain? could you undertain? could they undertain?	could I be undertaining? could you be undertaining? could he be undertaining? could we be undertaining? could you be undertaining? could they be undertaining?
Perfect	V-ing perfect
could I have undertained? could you have undertained? could he have undertained? could we have undertained? could you have undertained? could they have undertained?	could I have been undertaining? could you have been undertaining? could he have been undertaining? could we have been undertaining? could you have been undertaining? could they have been undertaining?

Interro-negative form

Simple form	V-ing form
could I not undertain? could you not undertain? could he not undertain? could we not undertain? could you not undertain? could they not undertain?	could I not be undertaining? could you not be undertaining? could he not be undertaining? could we not be undertaining? could you not be undertaining? could they not be undertaining?
Perfect	V-ing perfect
could I not have undertained? could you not have undertained? could he not have undertained? could we not have undertained? could you not have undertained? could they not have undertained?	could I not have been undertaining? could you not have been undertaining? could he not have been undertaining? could we not have been undertaining? could you not have been undertaining? could they not have been undertaining?