1) ALL sentences in the English language ALWAYS begin with a capital letter (uppercase).
2) In the English language, the pronoun 'I' is ALWAYS capitalized.
3) In the English language, the names of languages are ALWAYS capitalized.
4) In your post, you should have separated the two clauses with a comma, not with a period.
5) In your post, the word 'student' should have be pluralized.
6) Apparently, you do not possess the proper skills to teach English effectively. I would also lack motivation if I were one of your students. Please seek other employment.