まずは、point outっていう基本フレーズを覚えよう。 あと、私だったらあえて慇懃無礼な過剰丁寧な言い回しで相手の感情を逆撫でするね。 たとえば、 Your attention is directed to the fact とか。ビジネスレターでも使えそうな言い回しだ。 こんな感じかな。 Your attention is directed to the fact that your messages are filled with grammatically incorrect expressions and typographical errors, and thus, you are requested to refrain from posting such messages that causes readers to hardly appreciate the meanings thereof.