I could undermine you could undermine he could undermine we could undermine you could undermine they could undermine
V-ing form
I could be undermining you could be undermining he could be undermining we could be undermining you could be undermining they could be undermining
Perfect
I could have undermined you could have undermined he could have undermined we could have undermined you could have undermined they could have undermined
V-ing perfect
I could have been undermining you could have been undermining he could have been undermining we could have been undermining you could have been undermining they could have been undermining
Negation
Simple form
I could not undermine you could not undermine he could not undermine we could not undermine you could not undermine they could not undermine
V-ing form
I could not be undermining you could not be undermining he could not be undermining we could not be undermining you could not be undermining they could not be undermining
Perfect
I could not have undermined you could not have undermined he could not have undermined we could not have undermined you could not have undermined they could not have undermined
V-ing perfect
I could not have been undermining you could not have been undermining he could not have been undermining we could not have been undermining you could not have been undermining they could not have been undermining
Interrogative form
Simple form
could I undermine? could you undermine? could he undermine? could we undermine? could you undermine? could they undermine?
V-ing form
could I be undermining? could you be undermining? could he be undermining? could we be undermining? could you be undermining? could they be undermining?
Perfect
could I have undermined? could you have undermined? could he have undermined? could we have undermined? could you have undermined? could they have undermined?
V-ing perfect
could I have been undermining? could you have been undermining? could he have been undermining? could we have been undermining? could you have been undermining? could they have been undermining?
Interro-negative form
Simple form
could I not undermine? could you not undermine? could he not undermine? could we not undermine? could you not undermine? could they not undermine?
V-ing form
could I not be undermining? could you not be undermining? could he not be undermining? could we not be undermining? could you not be undermining? could they not be undermining?
Perfect
could I not have undermined? could you not have undermined? could he not have undermined? could we not have undermined? could you not have undermined? could they not have undermined?
V-ing perfect
could I not have been undermining? could you not have been undermining? could he not have been undermining? could we not have been undermining? could you not have been undermining? could they not have been undermining?