I started learning ASL formally about 12years ago and have been conversationally fluent for about 10 (I sucked up learning ASL like a parched sponge ...even though it's not my 1st language, it's the one that "makes sense" to me in a "native way"). The only thing that I really need to work on is number concepts (money, calendar dates) because I just don't use either very much, and improving my classifiers to an even more fluent level.
When I went back to university/seminary in 2006 I had ASL interpreters for all my classes - many of which had very specialized vocabulary both Signed and spoken so I utilized both the ASL as well as my residual hearing (to listen to the profs when possible) to maximize my understanding of the topics etc. It worked very well!
Unfortunately, I was injured a few years ago. This not only made signing painful, but muscle weakness meant I had to do a lot of PT to be able to sign at all (it's still painful +5years later). This meant that I was also unable to really participate in much of the activities etc in ASL (Hoh&Deaf) community - both because of the nature of the various activities, and because signing for extended periods (like an evening out) was very painful
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I ended up giving up my apt ($$ because haven't been able to work due to physical disability) and temporarily live with my mum (hearing) who doesn't sign very much at all... so my "conversationally fluent" ASL has gotten a bit "rusty" and is not as "smooth" as it was in the past.
My mum did take a number of ASL classes a few years back and for a while signed with me a lot (awesome, even if she signed very slowly). Slowly she's switched back to speaking all the time and has forgotten a LOT of the ASL she learnt. Part of the reason she started speaking more and signing less was back when I got my first HA I literally had to "re-learn how to hear" and asked her to help me practice listening by speaking for a while (meaning a few months while I adjusted)... unfortunately somehow this became a permanent switch back to speaking (you have no idea how much I wish I had NOT said anything about speaking and just let her continue signing
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