I used natural sea sponges to create the living coral reef.
(I; used; natural sea sponges; to create the living coral reef) Context(I used,List([0, 6))):(I; used natural sea sponges to create; the living coral reef)
I used,List([0, 6))
I I
used used natural sea sponges to create
natural sea sponges to create the living coral reef
the living coral reef