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