Abstract The relationship between the Songhay and Mande language families has fascinated West Africanists. The typological similarities run deep, but the respective lexicons are noncognate. I focus here on a typological rarity, a bidirectional case marker (BCM), namely Proto-Songhay *na and its descendants, and argue that it was most likely borrowed from Mande as part of the adoption by Songhay of the equally typologically rare Mande-type S(‑infl)‑O‑V‑X syntax, which reduces to S‑O‑V‑X when there is no post-subject inflectional morpheme (predicative marker). Apparently Songhay had little choice but to borrow the morpheme on the grounds that it did not previously possess the S(‑infl)‑O‑V‑X construction of which it is a key component, especially since a buffer between S and O prevents real-time mis-parsing of two adjacent NPs as possessor-possessum. The medial (‘caught in the middle’) position of the morpheme in the S‑BCM‑O sequence favored the borrowing, in spite of its abstract relational function which in some theoretical models should block borrowing.

中文翻译：

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被夹在中间

摘要Songhay和Mande语言家族之间的关系吸引了西非主义者。类型上的相似性很深，但是各自的词典是非同源的。在此，我将重点放在类型上的稀有性，即双向案例标记（BCM），即Proto-Songhay * na及其后代，并认为它很可能是从Mande借来的，这是Songhay采纳了同样在类型上稀有的Mande-类型S（‑infl）‑O‑V‑X语法，当没有主语后屈折语素（谓语标记）时，它会简化为S‑O‑V‑X。显然，Songhay别无选择，只能借用词素，理由是它以前不具有S（-infl）-O-V-X结构，而S（-infl）-O-V-X结构是关键组成部分，特别是因为S和O之间的缓冲区阻止了相邻两个NP的时间误解析为拥有者负。