Extraction shows important properties of coordination. Researchers noticed that in coordination it is not possible to extract a constituent from only one conjunct, but it is if the same element is moved out of both conjuncts. This is studied with the extraction of elements in content interrogatives [SYNTAX 1.2.3].
In LSC it is not possible to wh-extract an element from only one conjunct or from both ones using a single wh-sign either [SYNTAX 1.2.3.2]. In order to extract the same element, it is only possible to have the wh-sign at the end of each conjunct, as in the example (a) that follows. The answer can refer to the same element or to different ones. If an element is extracted only from one conjunct and the non-manual markers expressing a wh-question spread over both conjuncts, like in (b), the first one can only express a yes/no question. It is possible to see that in (a) and (b) the two clauses are anyway coordinated thanks to the presence of the characteristic non-manual markers found in coordination.
ht-left, bl-left ht-right, bl-right
fe fe
a) [mary buy what][contra] [jordi read what][ipsi]?
‘What did Marina buy and Jordi read?’
(© Giorgia Zorzi 2018. Reprinted with permission from Zorzi, 2018b: 154)
ht-left hl-right
fe
b) [marina buy][contra]? jordi read what?
‘Marina bought something? and what did Jordi read?’
(© Giorgia Zorzi 2018. Reprinted with permission from Zorzi, 2018b: 154)
In LSC, then, it is not possible to extract the same element from both conjuncts using wh-extraction. This test, then, is not good to test the presence of coordination in LSC.