Indefinite pronouns are typically used when the identity of the referent is unknown to the signer. For more details on indefiniteness, see PRAGMATICS 1.3.
In LIS, three indefinite pronouns are available: something, someone, and the sign person accompanied by particular non-manuals. The sign something is used for non-human unknown referents. It is a balanced two-handed sign that can undergo weak hand drop (PHONOLOGY 3.1.4).
something
The indefinite pronoun someone is compatible with human unknown referents. Phonologically, this sign is similar to cardinal one since it is articulated with extended index finger. This handshape is combined with an additional circular movement, which is the same observed in the articulation of something.
someone
Another sign that can be used to refer to a human unknown referent is person accompanied by special non-manuals conveying low referentiality, such as raised eyebrows, chin up (‘cu’), and mouth corners down (‘md’).
re
md
cu
person
‘Someone’
For more details on the use of this sign, the reader is referred to PRAGMATICS 1.5.