From the introduction: "It is evident that, despite a certain amount of word order freedom in Ancient Greek, there are also severe constraints on where words may occur. In this brief paper I present one such constraint and show how it affects the understanding of two verses which seem to be counterexamples to it (1 Cor 14:12 and 1 John 5:16)."
Marlett, Stephen A.
"Extraction from complement clauses in Koine Greek,"
Work Papers of the Summer Institute of Linguistics, University of North Dakota Session: Vol. 31, Article 2.
Available at: https://commons.und.edu/sil-work-papers/vol31/iss1/2