  In this paper we define almost gentle algebras. They are monomial special
multiserial algebras generalizing gentle algebras. We show that the trivial
extension of an almost gentle algebra by its minimal injective co-generator is
a symmetric special multiserial algebra and hence a Brauer configuration
algebra. Conversely, we show that any almost gentle algebra is an admissible
cut of a unique Brauer configuration algebra and as a consequence, we obtain
that every Brauer configuration algebra with multiplicity function identically
one, is the trivial extension of an almost gentle algebra. We show that to
every almost gentle algebra A is associated a hypergraph, and that this
hypergraph induces the Brauer configuration of the trivial extension of A.
Amongst other things, this gives a combinatorial criterion to decide when two
almost gentle algebras have isomorphic trivial extensions.
