English verb conjugation
COULD POSTDATE

Regular verb: postdate - postdated - postdated

Affirmation

Simple form	V-ing form
I could postdate you could postdate he could postdate we could postdate you could postdate they could postdate	I could be postdating you could be postdating he could be postdating we could be postdating you could be postdating they could be postdating
Perfect	V-ing perfect
I could have postdated you could have postdated he could have postdated we could have postdated you could have postdated they could have postdated	I could have been postdating you could have been postdating he could have been postdating we could have been postdating you could have been postdating they could have been postdating

Negation

Simple form	V-ing form
I couldn't postdate you couldn't postdate he couldn't postdate we couldn't postdate you couldn't postdate they couldn't postdate	I couldn't be postdating you couldn't be postdating he couldn't be postdating we couldn't be postdating you couldn't be postdating they couldn't be postdating
Perfect	V-ing perfect
I couldn't have postdated you couldn't have postdated he couldn't have postdated we couldn't have postdated you couldn't have postdated they couldn't have postdated	I couldn't have been postdating you couldn't have been postdating he couldn't have been postdating we couldn't have been postdating you couldn't have been postdating they couldn't have been postdating

Interrogative form

Simple form	V-ing form
could I postdate? could you postdate? could he postdate? could we postdate? could you postdate? could they postdate?	could I be postdating? could you be postdating? could he be postdating? could we be postdating? could you be postdating? could they be postdating?
Perfect	V-ing perfect
could I have postdated? could you have postdated? could he have postdated? could we have postdated? could you have postdated? could they have postdated?	could I have been postdating? could you have been postdating? could he have been postdating? could we have been postdating? could you have been postdating? could they have been postdating?

Interro-negative form

Simple form	V-ing form
couldn't I postdate? couldn't you postdate? couldn't he postdate? couldn't we postdate? couldn't you postdate? couldn't they postdate?	couldn't I be postdating? couldn't you be postdating? couldn't he be postdating? couldn't we be postdating? couldn't you be postdating? couldn't they be postdating?
Perfect	V-ing perfect
couldn't I have postdated? couldn't you have postdated? couldn't he have postdated? couldn't we have postdated? couldn't you have postdated? couldn't they have postdated?	couldn't I have been postdating? couldn't you have been postdating? couldn't he have been postdating? couldn't we have been postdating? couldn't you have been postdating? couldn't they have been postdating?