三語初階現象：類型學主導趨向、二語因素定向或是母語特徵導向？

L3 Initial State: Typological Primacy Driven, L2 Factor Determinded, or L1 Feature Oriented?

近年來，多語言和三語習得（L3）的觀察顯示：成人的三語習得不同於二語習得（L2）的原因是在語言遷移。二語習得的語言遷移現象涉及單一語言習得，但母語和二語習得在三語習得中是有效的。本文探討主要子句和嵌入句中空主語和空受語之代名詞現象。受試者是L2為進階英語的漢語成年者，並且分別習得初級法語和西語。這項研究用以測試三篇不同解釋三語初階之自然性的理論。Tsimpli與Dimitrakopoulou（2007）的《解釋性假設》對成年學習者於往後語言習得上提出明確聲明：後期語言習得上，成年學習者無法達到非解釋性上的句法特徵。Bardel與Falk（2007and2011）的《二語因素》反對母語遷移，並提出後天性二語的構詞句法特質使三語習得較易成功。最後Rothman（2011）的《類型學主導趨向》主張：三語習得和前期語言習得（L1或L2）在類型學上的相似性對語習遷移有決定性因素。此結論與《二語因素》和《解釋性假設》相似。學習者在主要子句和嵌入句中空主、受語情況的不對稱顯示：不但主、受語連主要子句和嵌入句都被第三語言是法語和西語的學習者做了不同的處理。Kong（2005）解釋了成年學習者無法達到非解讀性句法特徵。反之，中介語語法涉及漢語主題詞的使用。主題詞只要在每句之首，其他位置的論元則可被省略。

The present study investigates the interpretation of null subject and object pronouns in matrix and embedded clauses by twenty-five adult Chinese speakers of advanced L2 English acquiring L3 French in the initial stage and twenty-three participants of the same L1/L2 background acquiring L3 Spanish in the initial stage. It tests predictions made by three theories in L3 acquisition: the Typological Primacy Model of Rothman (2011), the L2 Status Factor of Bardel and Falk (2007) and Falk and Bardel (2011), and the Interpretability Hypothesis of Tsimpli and Dimitrakopoulou (2007). Asymmetries displayed in learners' interpretation of null matrix subjects and null embedded subjects as well as in null matrix subjects and null matrix and embedded objects suggest not only subjects and objects but also matrix and embedded clauses are treated differently by L1 Chinese/L2 English speakers of L3 French and L3 Spanish. The observed behaviour can be explained following Kong (2005) that adult learners have no access to uninterpretable syntactic features.