Hello, welcome to this poster! For the poster, please download the .pdf. You can watch the video on one side of your screen as you look at the poster on the other side. @[youtube](https://www.youtube.com/watch?v=LIs8fYLgziE) Thanks for watching, any questions and comments can be directed to Tory Sampson at tosampso at ucsd dot edu. ----------ABSTRACT---------- Previous literature in American Sign Language (ASL) has claimed that there is no copula in ASL [1]. However, corpus analyses reveal that there is a copula in ASL, expressed with the sign ‘SELF’, which specifically predicates individual-level predicates [2]. Individual-level predicates characterize traits inherent to the individual and are generally immutable (e.g., deaf) while stage-level predicates are temporally mutable (e.g., sit) [3]. We hypothesized that sentences with individual-level predicates need the copular SELF to satisfy sentential requirements, as in (1). This predicts that signers will prefer the copular SELF with individual-level predicates rather than any other possible copular signs, such as IX or null. For example, in (2) and (3), sentences with IX or null as the copula are not as grammatically acceptable as (1). (1) K-A-T-E SELF LAW+AGENT Kate is a lawyer. (2) ?*K-A-T-E IX LAW+AGENT (3) *K-A-T-E null LAW+AGENT We used a two-alternative forced choice grammatical acceptability task in which natively signing subjects were shown two signed sentences and asked to pick which is the most acceptable of the two. Stimulus sentences were comprised of varying permutations of two variables: copula type (SELF, IX, null) and predicate type (stage-level, individual-level). Paired sentences differed in only one variable (e.g., copula type: L-O-R-I SELF VOTE YESTERDAY vs. L-O- R-I IX VOTE YESTERDAY; predicate type: G-A-I-L SELF MOVIE DIRECT+AGENT vs. G-A-I-L SELF READ YESTERDAY). Pilot data to date show evidence supporting our hypothesis that the copular SELF is necessary in sentences with individual-level predicates. Participants generally preferred sentences in which the copula type SELF was paired with an individual-level predicate and when the copula type IX was paired with a stage-level predicate. Comparisons between SELF and null also showed preference for null to pair with stage-level predicates. References: [1] Bellugi & Fischer, 1972; Woodward, 1973; Stokoe, 1978; Fischer & Gough, 1978 [2] Sampson & Mayberry, submitted [3] Carlson 1977; Kratzer, 1995