I could relate you could relate he could relate we could relate you could relate they could relate
V-ing form
I could be relating you could be relating he could be relating we could be relating you could be relating they could be relating
Perfect
I could have related you could have related he could have related we could have related you could have related they could have related
V-ing perfect
I could have been relating you could have been relating he could have been relating we could have been relating you could have been relating they could have been relating
Negation
Simple form
I couldn't relate you couldn't relate he couldn't relate we couldn't relate you couldn't relate they couldn't relate
V-ing form
I couldn't be relating you couldn't be relating he couldn't be relating we couldn't be relating you couldn't be relating they couldn't be relating
Perfect
I couldn't have related you couldn't have related he couldn't have related we couldn't have related you couldn't have related they couldn't have related
V-ing perfect
I couldn't have been relating you couldn't have been relating he couldn't have been relating we couldn't have been relating you couldn't have been relating they couldn't have been relating
Interrogative form
Simple form
could I relate? could you relate? could he relate? could we relate? could you relate? could they relate?
V-ing form
could I be relating? could you be relating? could he be relating? could we be relating? could you be relating? could they be relating?
Perfect
could I have related? could you have related? could he have related? could we have related? could you have related? could they have related?
V-ing perfect
could I have been relating? could you have been relating? could he have been relating? could we have been relating? could you have been relating? could they have been relating?
Interro-negative form
Simple form
couldn't I relate? couldn't you relate? couldn't he relate? couldn't we relate? couldn't you relate? couldn't they relate?
V-ing form
couldn't I be relating? couldn't you be relating? couldn't he be relating? couldn't we be relating? couldn't you be relating? couldn't they be relating?
Perfect
couldn't I have related? couldn't you have related? couldn't he have related? couldn't we have related? couldn't you have related? couldn't they have related?
V-ing perfect
couldn't I have been relating? couldn't you have been relating? couldn't he have been relating? couldn't we have been relating? couldn't you have been relating? couldn't they have been relating?