It is necessary to capture the thin edge of the variants “нах@j” and “on x@j”. There is an expression of “nah@j”. It makes sense “why?” Also, there is an interdomain of the same name, which is used simply to connect words in a sentence. “Wear a hat, or you will get a cold.” Unlike the nickname, “on x@j” should be understood literally. In any case, there is a verification word “in pi@du”. If you doubt how to write properly, replace “on x@j” with “on pi@du”. If the meaning has not changed, it must be written separately. If "nah@y" can be painlessly deleted from the text, then it is written together and is highlighted, nah@y, closed.

C Fishki