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 couldn't post you couldn't post he couldn't post we couldn't post you couldn't post they couldn't post	I couldn't be posting you couldn't be posting he couldn't be posting we couldn't be posting you couldn't be posting they couldn't be posting
Perfect	V-ing perfect
I couldn't have posted you couldn't have posted he couldn't have posted we couldn't have posted you couldn't have posted they couldn't have posted	I couldn't have been posting you couldn't have been posting he couldn't have been posting we couldn't have been posting you couldn't have been posting they couldn't 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
couldn't I post? couldn't you post? couldn't he post? couldn't we post? couldn't you post? couldn't they post?	couldn't I be posting? couldn't you be posting? couldn't he be posting? couldn't we be posting? couldn't you be posting? couldn't they be posting?
Perfect	V-ing perfect
couldn't I have posted? couldn't you have posted? couldn't he have posted? couldn't we have posted? couldn't you have posted? couldn't they have posted?	couldn't I have been posting? couldn't you have been posting? couldn't he have been posting? couldn't we have been posting? couldn't you have been posting? couldn't they have been posting?