![](https://lemmy.sdf.org/pictrs/image/0d7b026b-610c-42ea-9afa-4b333d8d7c67.png)
![](https://l.roofo.cc/api/v3/image_proxy?url=https%3A%2F%2Flemmy.ml%2Fpictrs%2Fimage%2Fd3d059e3-fa3d-45af-ac93-ac894beba378.png)
Best sounding recommendation probably depends on context and ‘the thing’:
There’s a concept I don’t understand.
There is something in the box I don’t recognize.
There is a feature of the coffee machine I haven’t figured out yet.
There’s a Greek word in the original text that I don’t know.
To clarify - I think your proposed grammar is valid but the phrasing is uncommon. It’s not a phrase I would expect to hear. Though I would understand the gist of what you’re expressing.