Eve Ross - Beijing Institute of Machinery, China
My students use some of the most obscure English words I've ever seen, many that I've never heard of...and I consider myself to have a pretty sizeable vocabulary.
My personal rule of thumb is that if I don't recognize a word, most other English speakers probably won't know it, either, so why should the student use it? Especially at this stage of language learning, when native speakers struggle to understand them, due to syntax, pronunciation, and other errors?
Whenever I ask students where on earth they found such unusual words -- ones that most native speakers don't even use -- and the answer is inevitably the same. The Dictionary.
So I ask them what concept they were looking for. They'll usually tell me a Chinese word, which I've never (so far) known how to translate.
I ask them to tell me what it means. And they have always given me a clear, concise definition. Then a rhetorical question to the student: Why not trust your instincts rather than your dictionary, and use words that both you and your audience understand?