Learn Russian: Публикация обсуждается читателями. - The publication is discussed by the readers.

In Russian passive sentences, the agent (the person or thing doing the action) is expressed using just the Instrumental case. Adding a preposition for "by" is a common mistake for English speakers. Here, the noun читателями is in the Instrumental case, which naturally translates to "by the readers" all on its own.

How does the verb обсуждается become passive?

It uses the reflexive particle -ся. While -ся often indicates doing an action to oneself, it is also frequently used with imperfective verbs to form the passive voice. The active verb обсуждать (to discuss) simply adds this particle to become обсуждаться (to be discussed).

How is the Instrumental plural formed for the word читатель?

Читатель (reader) is a masculine noun that ends in a soft sign. To form the Instrumental plural, we drop the soft sign and add the soft ending -ями, giving us читателями. If it had ended in a hard consonant, it would take the hard ending -ами instead.

Would a Russian speaker use this exact structure in everyday conversation?

Usually, no. Passive sentences that combine a -ся verb with an Instrumental agent are perfectly correct but sound quite formal, journalistic, or bookish. In everyday speech, Russians strongly prefer the active voice: Читатели обсуждают публикацию (The readers are discussing the publication).