The nitrogen of pyridine and pyrrole is very different. Nitrogen of pyridine and a P electron participate in the formation of π bond, while pyrrole and a pair of electrons participate in the formation of large π bond. The former is an electron-deficient aromatic system, and the latter is an electron-rich aromatic system. The nitrogen atom of pyridine is unwilling to release electrons, while the nitrogen atom of pyrrole is generous. Back to the topic, I wonder if the questioner drew these * * * vibrations. If he did, the question is not difficult to explain at all. It can be seen that the ortho position of heteroatom is substituted, and the positive charge vibrates to nitrogen atom, which is eight electron nitrogen for pyrrole and six electron nitrogen for pyridine. Knowing octahedral theory is not difficult to compare who is more stable. Therefore, the ortho-para substitution of pyridine is unfavorable. Before the 20th century, organic matter lacked some systematic nomenclature, and was generally named by the author in the paper. After all, there is no concept of benzene ring, how to name it systematically = _ = Of course, people usually have etymological basis when naming it. Benzene is made from benzoic acid (also called benzoic acid) by Mitscherlich, and benzoic acid is made from benzoin resin. Benzoin was originally a spice in the15th century. It was called "Lubanjawi" by Arabs (a spice from Java) and then spread to Europe. Then, you should know that most parts of Europe pronounce Z as ts, and Rome and Greece distinguish aspirated sounds, so they are similar in theory. Naphthalene is taken from "naphtha" in English. This word is Naft in ancient Greece and Persia, which generally refers to oil. Anthracite comes from hard coal in English, and the word comes from the Greek word "coal" (? νθρακα? Phenanthrene is actually synthesized from phenyl and anthracene. The Frenchman Auguste Laurent synthesized benzene in Mitscherlich three years later. He named it phène, which was later used as the root of "phenyl". The word phène comes from the Greek Phaino, which means to shine, mainly to describe its burning.