xPlayer - the audio player with per-track bookmarks support. Play modes between bookmarks will be suitable for the language learners.
Features:

• add/remove unlimited number of per-track bookmarks,
• jump to a bookmark back and forth,
• different play modes: begin to end, between bookmarks one-time|/in cycle,
• “jump 5 seconds back” button,
• convinient big buttons “play-pause-back”