could undermine
Regular verb: undermine - undermined- undermined

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I could undermine
you could undermine
he could undermine
we could undermine
you could undermine
they could undermine 	I could be undermining
you could be undermining
he could be undermining
we could be undermining
you could be undermining
they could be undermining	I could have undermined
you could have undermined
he could have undermined
we could have undermined
you could have undermined
they could have undermined	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 	V-ing form 	Perfect 	V-ing perfect 	
I could not undermine
you could not undermine
he could not undermine
we could not undermine
you could not undermine
they could not undermine 	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	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	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 	V-ing form 	Perfect 	V-ing perfect 	
could I undermine?
could you undermine?
could he undermine?
could we undermine?
could you undermine?
could they undermine? 	could I be undermining?
could you be undermining?
could he be undermining?
could we be undermining?
could you be undermining?
could they be undermining? 	could I have undermined?
could you have undermined?
could he have undermined?
could we have undermined?
could you have undermined?
could they have undermined? 	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 	V-ing form 	Perfect 	V-ing perfect 	
could I not undermine?
could you not undermine?
could he not undermine?
could we not undermine?
could you not undermine?
could they not undermine? 	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? 	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? 	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?