本文介紹四川阿壩州黑水縣沙石多鄉嘉戎語動詞人稱範疇「雙重人稱標記」、「主語式對諧」、 及「與格論元掌控對諧」三項醒目特徵，並通過親屬語言比較及語意因素辨析，探索其歷史源流與類 型意義。「雙重人稱標記」顯係古嘉戎語形態遺留，而「主語式對諧」及「與格論元掌控對諧」為朝 向「附屬語加標記」語法格局之類型遞變，應屬受本縣主流語言羌語深度接觸影響誘發的創新發展。 依據 Tsunoda (1985)，及物動詞賓語受影響之程度會造成形態句法的差異，及物性越高動詞越可能採用 「及物性框架」與被動、反被動等及物構造。本文對此提供進一步的佐證，同時指出：動詞對諧模式 的選擇也是檢驗及物性高低的另一重要類型學參項。

This study analyses three remarkable features in the person marking system of Sastod Rgyalrong spoken in Khrochu (Heishui) County of Aba Prefecture in northern Sichuan: double person marking, S/A subject agreement (as opposed to the Pan-Rgyalrongic scenario-driven split agreement), and dative-marked arguments as agreement controllers. Co mparison with other Rgyalrong languages and exploration of semantic factors underlying the distribution of predicate types that require subject agreement and dative marking reveal the possible evolution and typological significance of the phenomena under study. Double person marking in Sastod Rgyalrong appears to continue an archaic morphological trait. On the other hand, subject agreement and core dative marking appear to be innovative developments induced by intense contact with Qiang, embodying a typological shift towards a dependent-marking grammatical profile. Our findings not only lend strong support to Tsunoda’s insights regarding the repercussions of objectaffectedness on syntactic structure, but also contribute significantly to them by demonstrating that, in addition to transitive case frames and syntactic constructions like the passive and antipassive, selection between agreement patterns is another valid cross-linguistic correlate of the affectedness scale of transitive predicates.