Question

what is a verb form ending in -ing that is used as a noun?

Answer 1

Spelling is an example. "Spell" is a verb, but when you put "ing" on the end, it becomes a noun--or a verb still, depending on the context.

Answer 2

Write- verb
Writing-noun

Talk-verb
Talking-noun

Help-verb
Helping-noun......so on and so on

Answer 3

Helping isn't a noun... And writing and talking depend.

Answer 4

go see
http://dictionary.reference.com/