The audio player will stay in view as you scroll down. As the audio plays, the text will be highlighted. If you want to 'pause' or 'repeat' a sentence, it's very simple. Use 'Ctrl' for 'pause/play' and you can single click on any text and the audio will play that line. To then pause it and give you extra time to try saying it, hit 'Ctrl'. You can also slow down (or speed up) the audio using the 'slider' below the audio player.
If the video or control features don't work, please upgrade your browser or try Google Chrome. All the code is standard html5 which some old browsers don't recognize.