English verb conjugation
COULD POST

Regular verb: post - posted - posted

Affirmation

Simple form	V-ing form
I could post you could post he could post we could post you could post they could post	I could be posting you could be posting he could be posting we could be posting you could be posting they could be posting
Perfect	V-ing perfect
I could have posted you could have posted he could have posted we could have posted you could have posted they could have posted	I could have been posting you could have been posting he could have been posting we could have been posting you could have been posting they could have been posting

Negation

Simple form	V-ing form
I could not post you could not post he could not post we could not post you could not post they could not post	I could not be posting you could not be posting he could not be posting we could not be posting you could not be posting they could not be posting
Perfect	V-ing perfect
I could not have posted you could not have posted he could not have posted we could not have posted you could not have posted they could not have posted	I could not have been posting you could not have been posting he could not have been posting we could not have been posting you could not have been posting they could not have been posting

Interrogative form

Simple form	V-ing form
could I post? could you post? could he post? could we post? could you post? could they post?	could I be posting? could you be posting? could he be posting? could we be posting? could you be posting? could they be posting?
Perfect	V-ing perfect
could I have posted? could you have posted? could he have posted? could we have posted? could you have posted? could they have posted?	could I have been posting? could you have been posting? could he have been posting? could we have been posting? could you have been posting? could they have been posting?

Interro-negative form

Simple form	V-ing form
could I not post? could you not post? could he not post? could we not post? could you not post? could they not post?	could I not be posting? could you not be posting? could he not be posting? could we not be posting? could you not be posting? could they not be posting?
Perfect	V-ing perfect
could I not have posted? could you not have posted? could he not have posted? could we not have posted? could you not have posted? could they not have posted?	could I not have been posting? could you not have been posting? could he not have been posting? could we not have been posting? could you not have been posting? could they not have been posting?