Hi, Sandra,
Here is the reference letter I wrote about you.
Sandra helped me to fix my pronunciation and improve my speaking. Her explanations are always clear and easy to understand. After I studied with Sandra, I had confidence in my pronunciation and became able to speak  more. Also, the speaking lesson with a movie helped me to speak and explain situations using reported speech and long sentences .
I took an interpretation and translation course in one school after taking Sandra's lesson. The contents and level of that course were quite difficult and high.  If I didn't take Sandra's lesson, I couldn't keep up with that interpretation class.
If you have a motivation in which you really want to improve your pronunciation and speaking and also if you review many times what you learned from Sandra, she absolutely will help you to improve them. She is a great teacher! I really appreciate her.