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