head directionality parameter
Definition - A parameter setting that classifies word order according to the placement of the head. This setting can be either:

(1) Head-final, where the head appears at the end of phrases — for example, the German "Jan hat das Buch auf den Tisch gelegt" (John-has the-book on-the-table put.)

(2) Head-initial, where the head appears at the beginning of the phrase — for example, the English "John has put the book on the table."

1. Problem: The syntax of many languages is not consistently either head initial or head final.

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