subsheaf of free sheaves

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Let $X$ be an irreducible nodal curve, $E:=\oplus_{i=1}^r \mathcal{O}_X$ be a free sheaf on $X$ and $F \subset E$ a (coherent) subsheaf. Is it possible to write $F$ as a direct sum of subsheaves $F_1,..,F_j$ for $j \le r$ such that $F_i \subset \mathcal{O}_X$? Can we take $F_i$ to be the image of $F$ under the composition $F \to E \xrightarrow{\mathrm{pr}_i} \mathcal{O}_X$, where $\mathrm{pr}_i$ is the projection onto the $i$-th coordinate.