Meaning of ならずとも This sentence is from a book about Japanese grammar written for native Japanese speakers: * The refers to a past incident where a Japanese teacher's explanation of the particle to foreigners ended up being confusing and incomplete. * Teramura-sensei is a Japanese teacher who the book refers to as a pioneer in Japanese language teaching. "Incidentally, incidents like this are probably encountered by many Japanese teachers, and not just Teramura-sensei." seems like a reasonable translation, but I don't know what's going on with that If it means "" then I would expect to see a or just before () but that doesn't seem to be the case. Can anyone clarify what that is signifying? Thanks in advance.

This is a negated form of the literary copula (fused from ). It's not the verb "become", so inserting or wouldn't be appropriate. Here, it attaches directly to the noun phrase .

The literary form generally means roughly , so the literal meaning of is close to the colloquial "even if it isn't". This phrase is used to mean something like , "others besides ..." or "in addition to ...".

This is covered in Martin's 1975 _Reference Grammar of Japanese_ , p.368 and p.1010.