Warning, this verb may not exist. Conjugation is given as example.
Affirmation
Simple form
I could etch etch you could etch etch he could etch etch we could etch etch you could etch etch they could etch etch
V-ing form
I could be etch etching you could be etch etching he could be etch etching we could be etch etching you could be etch etching they could be etch etching
Perfect
I could have etch etched you could have etch etched he could have etch etched we could have etch etched you could have etch etched they could have etch etched
V-ing perfect
I could have been etch etching you could have been etch etching he could have been etch etching we could have been etch etching you could have been etch etching they could have been etch etching
Negation
Simple form
I could not etch etch you could not etch etch he could not etch etch we could not etch etch you could not etch etch they could not etch etch
V-ing form
I could not be etch etching you could not be etch etching he could not be etch etching we could not be etch etching you could not be etch etching they could not be etch etching
Perfect
I could not have etch etched you could not have etch etched he could not have etch etched we could not have etch etched you could not have etch etched they could not have etch etched
V-ing perfect
I could not have been etch etching you could not have been etch etching he could not have been etch etching we could not have been etch etching you could not have been etch etching they could not have been etch etching
Interrogative form
Simple form
could I etch etch? could you etch etch? could he etch etch? could we etch etch? could you etch etch? could they etch etch?
V-ing form
could I be etch etching? could you be etch etching? could he be etch etching? could we be etch etching? could you be etch etching? could they be etch etching?
Perfect
could I have etch etched? could you have etch etched? could he have etch etched? could we have etch etched? could you have etch etched? could they have etch etched?
V-ing perfect
could I have been etch etching? could you have been etch etching? could he have been etch etching? could we have been etch etching? could you have been etch etching? could they have been etch etching?
Interro-negative form
Simple form
could I not etch etch? could you not etch etch? could he not etch etch? could we not etch etch? could you not etch etch? could they not etch etch?
V-ing form
could I not be etch etching? could you not be etch etching? could he not be etch etching? could we not be etch etching? could you not be etch etching? could they not be etch etching?
Perfect
could I not have etch etched? could you not have etch etched? could he not have etch etched? could we not have etch etched? could you not have etch etched? could they not have etch etched?
V-ing perfect
could I not have been etch etching? could you not have been etch etching? could he not have been etch etching? could we not have been etch etching? could you not have been etch etching? could they not have been etch etching?