Warning, this verb may not exist. Conjugation is given as example.
Affirmation
Simple form
I could stock stock you could stock stock he could stock stock we could stock stock you could stock stock they could stock stock
V-ing form
I could be stock stocking you could be stock stocking he could be stock stocking we could be stock stocking you could be stock stocking they could be stock stocking
Perfect
I could have stock stocked you could have stock stocked he could have stock stocked we could have stock stocked you could have stock stocked they could have stock stocked
V-ing perfect
I could have been stock stocking you could have been stock stocking he could have been stock stocking we could have been stock stocking you could have been stock stocking they could have been stock stocking
Negation
Simple form
I couldn't stock stock you couldn't stock stock he couldn't stock stock we couldn't stock stock you couldn't stock stock they couldn't stock stock
V-ing form
I couldn't be stock stocking you couldn't be stock stocking he couldn't be stock stocking we couldn't be stock stocking you couldn't be stock stocking they couldn't be stock stocking
Perfect
I couldn't have stock stocked you couldn't have stock stocked he couldn't have stock stocked we couldn't have stock stocked you couldn't have stock stocked they couldn't have stock stocked
V-ing perfect
I couldn't have been stock stocking you couldn't have been stock stocking he couldn't have been stock stocking we couldn't have been stock stocking you couldn't have been stock stocking they couldn't have been stock stocking
Interrogative form
Simple form
could I stock stock? could you stock stock? could he stock stock? could we stock stock? could you stock stock? could they stock stock?
V-ing form
could I be stock stocking? could you be stock stocking? could he be stock stocking? could we be stock stocking? could you be stock stocking? could they be stock stocking?
Perfect
could I have stock stocked? could you have stock stocked? could he have stock stocked? could we have stock stocked? could you have stock stocked? could they have stock stocked?
V-ing perfect
could I have been stock stocking? could you have been stock stocking? could he have been stock stocking? could we have been stock stocking? could you have been stock stocking? could they have been stock stocking?
Interro-negative form
Simple form
couldn't I stock stock? couldn't you stock stock? couldn't he stock stock? couldn't we stock stock? couldn't you stock stock? couldn't they stock stock?
V-ing form
couldn't I be stock stocking? couldn't you be stock stocking? couldn't he be stock stocking? couldn't we be stock stocking? couldn't you be stock stocking? couldn't they be stock stocking?
Perfect
couldn't I have stock stocked? couldn't you have stock stocked? couldn't he have stock stocked? couldn't we have stock stocked? couldn't you have stock stocked? couldn't they have stock stocked?
V-ing perfect
couldn't I have been stock stocking? couldn't you have been stock stocking? couldn't he have been stock stocking? couldn't we have been stock stocking? couldn't you have been stock stocking? couldn't they have been stock stocking?