Most people are familiar with sign language, the system that deaf people use to communicate. What fewer may know is that there are many different sign languages around the world, just as there are many different spoken languages.
So how does the grammar of sign language work?
Unlike in spoken languages, in which grammar is expressed through sound-based signifiers for tense, aspect, mood and syntax (the way we organise individual words), sign languages use hand movements, sign order as well as body and facial cues to create grammar. This is called non-manual activity.
To find out whether these cues are comprehensible to signers and non-signers of a country, my team of deaf and hearing linguists and translators conducted two studies. The results, which will be published in July, demonstrate the incredible complexity of sign language.
Read more: The Conversation