The mantle is important in snails because it secretes the shell, and it is thought to provide some protection for slugs.
(The mantle; is; important in snails; because it secretes the shell) (it; secretes; the shell) (it; to provide; some protection for slugs)
The mantle it it
is secretes to provide
important in snails because it secretes the shell
the shell
some protection for slugs