*3.2. Participants*

Twelve deaf bilingual signers (5 female: 7 male) were recruited for this study, ranging in age from 22 to 46 years (average age: 29 years). All participants are self-reported KQSL-ISL sign-bilinguals, and this was further corroborated by our deaf contact person from the community who is also a KQSL-ISL sign-bilingual. Participants completed a questionnaire about their family background, language preferences and use, and educational experience. They all grew up in Kufr Qassem, exposed to KQSL in the community and/or through family and friends. Most participants graduated from different mainstream high schools where the language of instruction was predominantly ISL. Participant 01 received formal education in the first deaf class before ISL was introduced, and she reported that she acquired ISL later in life through friends and social interaction with the wider deaf community. Some were taught in designated deaf classes in mainstream schools, while others had access to an ISL interpreter in the classroom. Participant characteristics are summarized in Table 4.


**Table 4.** Participant characteristics.

In addition to the twelve deaf bilinguals, two sign-monolinguals were recruited to act as consistent conversational partners in the semi-spontaneous task, described in Section 3.3 below. Each of these conversational partners represented a different language condition, one for KQSL and one for ISL. The KQSL sign-monolingual (female, 44 years old) is a second-generation deaf KQSL signer with KQSL as her first language, who attended the deaf class in Kufr Qassem when ISL was ye<sup>t</sup> not used. The ISL sign-monolingual (female, 31 years old) is a deaf ISL signer (ISL as her first language) from a deaf family with no previous knowledge of KQSL. Each of the monolinguals were instructed to use their L1 sign languages and to simply engage in the conversational task with each new participant.

Filming took place in the deaf club in Kufr Qassem. A deaf contact person was responsible for recruiting participants and running the tasks. Participants signed a consent form before taking part in this study. Consent forms and questionnaire were offered in Arabic and in Hebrew, and all instructions were explained to the participants in their preferred language. This study was approved by the Ethics Committee at Bar-Ilan University. All participants were compensated for their time.
