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