Agreement verbs (LEXICON 3.2.2) mark duality through i) addition of the non-dominant hand in one-handed signs or ii) reduplication of the verb, whose starting and ending point of articulation can be changed in order to convey duality of the subject or object. Example (a) shows that the verb agrees with the dual object being articulated as a two-handed sign; (b) displays the same strategy employed to mark duality of the subject, whereas (c) is an example of reduplication of the verb to convey duality of the object.
a. dom: g-i-u-l-i-aa m-a-r-i-ab g-i-a-n-n-ic book cgiveb
n-dom: cgivea
‘Gianni gives one book to Giulia and Maria respectively.’
b. dom: g-i-u-l-i-aa m-a-r-i-ab bphone_call1
n-dom: aphone_call1
‘Giulia and Maria call me.’
c. ix1 g-i-u-l-i-aa m-a-r-i-ab 1phone_calla 1phone_callb
‘I call Giulia and Maria on the phone.’
In the same vein, backward verbs can mark duality of the source/object which is being copied, chosen or invited. The example below shows the reduplication of the backward verb sign copy to convey duality of the source.
book two CL(unspread 5): ‘book’ aCL(unspread 5): ‘book’b student acopy bcopy
‘The student copies (a text) from two books.’
The same strategies are employed by that subclass of agreeing verbs displaying only one point of articulation in the signing space corresponding to their single argument. The example below shows that the one-handed verb grow_up becomes a two-handed symmetrical sign in order to convey duality of the subject.
dom: childa childb two grow_upb
n-dom: grow_upa
‘The two children are growing up.’