>165
添削してあげる。
You had better not [ to] abuse him though I have never read his responses in detail.
You (had better ) [should] know etiquette is necessary (even if) [ when ] you face
an ignorant person though it is interesting to tease (a fool)[him or her].
Of course, I think that you understand (all) [ all that]

全体的にこなれていない文章。それでも原文を尊重して直してみたよ。
英検準1級位の英文力かね。.