Vector spaces/Direct sum/Residue class space/Exercise

Suppose that the ${}K$-vector space ${}V$ is the direct sum of the linear subspaces ${}V_{1}$ and ${}V_{2}$, and let ${}U_{1}\subseteq V_{1}$ and ${}U_{2}\subseteq V_{2}$ be linear subspaces. Show that

${}V_{1}\oplus V_{2}/{\left(U_{1}\oplus U_{2}\right)}\cong V_{1}/U_{1}\oplus V_{2}/U_{2}\,.$

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