Remark 1.1.4.3. Let $m$ and $n$ be integers with $m \leq n$. Then, for every simplicial set $S$, the $m$-skeleton $\operatorname{sk}_{m}(S)$ is contained in the $n$-skeleton $\operatorname{sk}_{n}(S)$.
$\Newextarrow{\xhookrightarrow}{10,10}{0x21AA}$