  B\`{e}s and Choffrut recently showed that there are no intermediate
structures between $(\mathbb{R},<,+)$ and $(\mathbb{R},<,+,\mathbb{Z})$. We
prove a generalization: if $\mathcal{R}$ is an o-minimal expansion of
$(\mathbb{R},<,+)$ by bounded subsets of Euclidean space then there are no
intermediate structures between $\mathcal{R}$ and $(\mathcal{R},\mathbb{Z})$.
It follows there are no intermediate structures between
$(\mathbb{R},<,+,\sin|_{[0,2\pi]})$ and $(\mathbb{R},<,+,\sin)$.
