English verb conjugation
COULD UNDERTAIN

Regular verb: undertain - undertained - undertained

Affirmation

Simple form	V-ing form
I could undertain you could undertain she could undertain we could undertain you could undertain they could undertain	I could be undertaining you could be undertaining she 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 she 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 she 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 couldn't undertain you couldn't undertain she couldn't undertain we couldn't undertain you couldn't undertain they couldn't undertain	I couldn't be undertaining you couldn't be undertaining she couldn't be undertaining we couldn't be undertaining you couldn't be undertaining they couldn't be undertaining
Perfect	V-ing perfect
I couldn't have undertained you couldn't have undertained she couldn't have undertained we couldn't have undertained you couldn't have undertained they couldn't have undertained	I couldn't have been undertaining you couldn't have been undertaining she couldn't have been undertaining we couldn't have been undertaining you couldn't have been undertaining they couldn't have been undertaining

Interrogative form

Simple form	V-ing form
could I undertain? could you undertain? could she undertain? could we undertain? could you undertain? could they undertain?	could I be undertaining? could you be undertaining? could she 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 she 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 she 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
couldn't I undertain? couldn't you undertain? couldn't she undertain? couldn't we undertain? couldn't you undertain? couldn't they undertain?	couldn't I be undertaining? couldn't you be undertaining? couldn't she be undertaining? couldn't we be undertaining? couldn't you be undertaining? couldn't they be undertaining?
Perfect	V-ing perfect
couldn't I have undertained? couldn't you have undertained? couldn't she have undertained? couldn't we have undertained? couldn't you have undertained? couldn't they have undertained?	couldn't I have been undertaining? couldn't you have been undertaining? couldn't she have been undertaining? couldn't we have been undertaining? couldn't you have been undertaining? couldn't they have been undertaining?