English verb conjugation
COULD SQUARE

Regular verb: square - squared - squared

Affirmation

Simple form	V-ing form
I could square you could square she could square we could square you could square they could square	I could be squaring you could be squaring she could be squaring we could be squaring you could be squaring they could be squaring
Perfect	V-ing perfect
I could have squared you could have squared she could have squared we could have squared you could have squared they could have squared	I could have been squaring you could have been squaring she could have been squaring we could have been squaring you could have been squaring they could have been squaring

Negation

Simple form	V-ing form
I could not square you could not square she could not square we could not square you could not square they could not square	I could not be squaring you could not be squaring she could not be squaring we could not be squaring you could not be squaring they could not be squaring
Perfect	V-ing perfect
I could not have squared you could not have squared she could not have squared we could not have squared you could not have squared they could not have squared	I could not have been squaring you could not have been squaring she could not have been squaring we could not have been squaring you could not have been squaring they could not have been squaring

Interrogative form

Simple form	V-ing form
could I square? could you square? could she square? could we square? could you square? could they square?	could I be squaring? could you be squaring? could she be squaring? could we be squaring? could you be squaring? could they be squaring?
Perfect	V-ing perfect
could I have squared? could you have squared? could she have squared? could we have squared? could you have squared? could they have squared?	could I have been squaring? could you have been squaring? could she have been squaring? could we have been squaring? could you have been squaring? could they have been squaring?

Interro-negative form

Simple form	V-ing form
could I not square? could you not square? could she not square? could we not square? could you not square? could they not square?	could I not be squaring? could you not be squaring? could she not be squaring? could we not be squaring? could you not be squaring? could they not be squaring?
Perfect	V-ing perfect
could I not have squared? could you not have squared? could she not have squared? could we not have squared? could you not have squared? could they not have squared?	could I not have been squaring? could you not have been squaring? could she not have been squaring? could we not have been squaring? could you not have been squaring? could they not have been squaring?