I hope that you’re not having many grammar problems so far, but just in case you need to revise a little… here you have a few interesting links.
- If you feel you are still making many mistakes with the Present Simple, then, please revise them in these two pages from englishpage. Then do some practice exercises here, here and here. They are from better-english.com.
- If you need to review the present & the past, englishpage offers you this to help you a bit, and this includes non-continuous verbs (interesting).
- For extensive general practice of varied tenses, go to nonstopenglish.
Have a good weekend!