ring species

As an electrophilic agent, the methyl group of methoxy species can directly attack benzene ring to produce toluene via electrophilic substitution reaction.

甲氧基物种的甲基作为一种亲电试剂，可以直接进攻苯环发生亲电取代烷基化反应生成甲苯。

Tree Sparrow, Magpie, Great Spotted Woodpecker, Ring Dove and Hoopoe can be applied as indicator species to estimate the quality of the urban environment.

树麻雀、喜鹊、大斑啄木鸟、灰斑鸠、戴胜5种鸟可作为城市环境的指示物种。

Bright and transparent, crystal smooth, transparent, glass species, emerald green, jade ring surface high-grade, two little difference in size!

明亮通透，晶莹光滑，透明，玻璃种，翠绿色，高档翡翠戒面，2颗的大小有点差别！

Also , the substituent species and the position on phenyl ring effects the reaction.

苯环上取代基的种类及位置对反应也有影响.