"do" and "don't".
-Go to this site for a video: click here
-Go to this site for some practice: click here
-Go to this site to review the structure of the simple present tense: Click here
2. Simple Present--questions that use who/what/where/when/why
-click here for more online practice: Note: At the bottom of the page, it says "next exercise", so continue to practice.
"have, has and had"
-Go to this site for a video: click here