Click on any word - the sound track will begin at that location.
Press back or forward arrow - The sound track will jump back or forward by three seconds. If paused the previous or next three words will be selected and the recording will begin at that location when played.
Press Number keys (1 -9) - Pressing 5 will cause the sound track to jump back five seconds.
Pressing the space bar will toggle between playing and pausing the sound track. (Of course you can also click on the Play / Pause button.) When paused the word that is being said is selected along with previous and next one.
Place the cursor over a punctuation mark to see the translation, or over an underlined word or phrase to see its definition.