English verb conjugation
COULD INTERPOLATE

Regular verb: interpolate - interpolated - interpolated

Affirmation

Simple form	V-ing form
I could interpolate you could interpolate he could interpolate we could interpolate you could interpolate they could interpolate	I could be interpolating you could be interpolating he could be interpolating we could be interpolating you could be interpolating they could be interpolating
Perfect	V-ing perfect
I could have interpolated you could have interpolated he could have interpolated we could have interpolated you could have interpolated they could have interpolated	I could have been interpolating you could have been interpolating he could have been interpolating we could have been interpolating you could have been interpolating they could have been interpolating

Negation

Simple form	V-ing form
I couldn't interpolate you couldn't interpolate he couldn't interpolate we couldn't interpolate you couldn't interpolate they couldn't interpolate	I couldn't be interpolating you couldn't be interpolating he couldn't be interpolating we couldn't be interpolating you couldn't be interpolating they couldn't be interpolating
Perfect	V-ing perfect
I couldn't have interpolated you couldn't have interpolated he couldn't have interpolated we couldn't have interpolated you couldn't have interpolated they couldn't have interpolated	I couldn't have been interpolating you couldn't have been interpolating he couldn't have been interpolating we couldn't have been interpolating you couldn't have been interpolating they couldn't have been interpolating

Interrogative form

Simple form	V-ing form
could I interpolate? could you interpolate? could he interpolate? could we interpolate? could you interpolate? could they interpolate?	could I be interpolating? could you be interpolating? could he be interpolating? could we be interpolating? could you be interpolating? could they be interpolating?
Perfect	V-ing perfect
could I have interpolated? could you have interpolated? could he have interpolated? could we have interpolated? could you have interpolated? could they have interpolated?	could I have been interpolating? could you have been interpolating? could he have been interpolating? could we have been interpolating? could you have been interpolating? could they have been interpolating?

Interro-negative form

Simple form	V-ing form
couldn't I interpolate? couldn't you interpolate? couldn't he interpolate? couldn't we interpolate? couldn't you interpolate? couldn't they interpolate?	couldn't I be interpolating? couldn't you be interpolating? couldn't he be interpolating? couldn't we be interpolating? couldn't you be interpolating? couldn't they be interpolating?
Perfect	V-ing perfect
couldn't I have interpolated? couldn't you have interpolated? couldn't he have interpolated? couldn't we have interpolated? couldn't you have interpolated? couldn't they have interpolated?	couldn't I have been interpolating? couldn't you have been interpolating? couldn't he have been interpolating? couldn't we have been interpolating? couldn't you have been interpolating? couldn't they have been interpolating?