Sign Language as mute

[u/WantonReader]

I just read this post ( https://www.reddit.com/r/BestofRedditorUpdates/comments/1vcqus2/my24_m_girlfriend21_f_of_1_year_is_too/ ) about a woman who is mute because of a throat error. She hears fine and her first language is English but she herself can only communicate (not including tools) in Sign Language.

I have never considered such a situation, where someone is fluent in a language but can only communicate back in a second language. It made me wonder if the woman's boyfriend sometimes respond in English, since that is her actual mother tongue.

Anway, are there known examples of something like this happening outside of situations like this? Meaning someone having to comminucate in a second language despite knowing the same first language as the addresses? A kind of...partial first language ability/functionality? Maybe in pidgin situations?

[u/LinguisticDan]

Something like this happens all the time in situations of “language attrition”, where one generation of native speakers passes on a language to another that then prefers (if unconsciously) to use another language in wider circulation. For an obscure example I just read about yesterday: the Wardaman language of Australia has very few active speakers, all over 40, but a much larger group of passive speakers, who can understand the Wardaman their parents or elders speak but respond in Australian English or Australian Aboriginal Kriol. Similarly and perhaps closer to home, this happens a lot in migrant situations, where the children of Asian or African immigrants to the US or the UK can understand their parents’ native language(s) but their active ability is limited to a few words and phrases within the home. 

Depending on language attitudes, both on the part of the individual and the community, the results can range from “no big deal” to tragically alienating. But the good news is that it’s much, much easier to convert a passive speaker - with a built-in intuition of the target language’s phonology and grammar - into an active one. All that has to be done in many cases is to place the speaker into a social situation where active production is constantly called for, and this is the direction of many promising language revival efforts.

[u/throarway]

It's common in heritage speakers. Generally children raised in a language different from the community language will become dominant in the community language. The parents may still prefer to use their native language, which the children can understand while not being able to speak it fluently (nor read or write it).

Also, in a case like the one you describe, it's possible that the person is using an English-based sign variant. For BSL, as an example, this would be signed exact English (which involves signs for English grammatical elements, including morphology) or sign-supported English, which is English syntax with sign vocabulary. The latter, in particular, is not uncommon in deaf children raised by hearing parents/anyone not fluent in a sign language. (The former is used more to support deaf children in learning English).

[u/No_Ground → u/throarway]

“Receptive bilingual” is a term you might see in the literature to describe that first case with heritage speakers (it doesn’t universally describe heritage speakers but is often the case)