I grew up and was educated at a time when correct writing was expected. My spelling and grammar are impeccable (including familiarity with subjunctive), I have a wide vocabulary, and I revise and edit my own essays and letters before submitting. I have published letters and articles in newspapers.
As a schoolteacher, I have developed writing skills in my students, encouraging them to word their paragraphs more clearly and succinctly, and discouraging them from plagiarism and ambiguity. Professors have told me that I write well; serious writing was required of me as a graduate student. I have a Master's degree in education and have taught Life Science for many years.
Errors in writing always catch my eye, and I would love to fix everyone's mistakes. Alas, not everyone asks. I shall be glad to advise you on improving and correcting your writing. If you need more help than just advice, I am your woman.