THIS LESSON TEACHES YOU TO CREATE SPEECH MOVEMENTS WITH THE MUSCLES IN THE REAR TONGUE, WHILE CONTINUING TO RELAX THE LIPS AND FRONT MOUTH.
This lesson is extremely important. Here's where you learn how the different parts of your muth should feel when you use the American style of muscle movement. Follow the instructions on the tape very closely. You'll begin by learning to glide your tongue from the AH-position (that you created in the last lesson) into a sharp EE-sound. Most importantly, you will learn how to control this movement with the muscles in the back of the tongue. You will then learn to modify this "AH-EE" combination by using what I call the QUICK AMERICAN GLIDE. In this special form, the first stage (AH) takes more time than the last stage (EE). In addition, the pitch of your voice glides down notice- ably as you begin the second stage of the sound. Make sure you learn to do this QUICK AMERICAN GLIDE extremely well. It will be particularly important in Lesson #5 when you study the Amer- ican pronunciations of the five diphthongs (double vowels). In order for them to sound really American, all five of them will have to contain the very same tongue movement and downward glide in pitch.
Finally, Lesson #4 gives you the opportunity to use the new muscle movements in other sound combinations and words. You'll begin by producing relaxed consonants at the end of the AH-EE glide. Next, you'll attach the relaxed consonant sounds at the beginning of the glide. At this point, you'll have to pay very close attention to how your tongue feels during this type of movement. Your next task will be to reproduce that feeling when you are combining other sounds. You'll use that new style of muscle movement while speaking again the words for the numbers 1-10, the days of the week, and the months of the year. Once again, follow the directions on the tape very closely as you practice the exercises in Less #4 several times.内容来自 听力课堂网：http://www.tingclass.net/show-6145-30316-1.html