investigate a Grassmann space as $\A$. It is known that every maximal strong subspace of a Grassmann space is a projective space. This, together with some additional assumptions, lets us apply the result obtained for projective spaces to recover the whole $\A$ and its horizon $\W$ in terms of the complement $\fixoutf(\A,\W)$. That way another affirmative answer to our question is formulated in Theorem \[thm:main-grass\].

At the end we give some examples where our results can be applied or not.

Generalities
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A point-line structure $\A=\struct{S, \lines}$, where the elements of $S$ are called *points*, the elements of $\lines$ are called *lines*, and where $\lines\subset2^S$, is said to be a *partial linear space*, or a *point-line space*, if two distinct lines share at most one point and every line is of size (cardinality) at least 2 (cf. [@cohen]). The incidence relation between points and lines is basically the membership relation $\in$.

For distinct points $a, b\in S$ we say that they are *adjacent* (*collinear*) and write $a\adjac b$ if there is a line in $\lines$ through $a, b$. The line through distinct points $a, b$ will be written as $\LineOn(a, b)$. For distinct lines $k, l\in\lines$ we say that they 