Refill Hearts
Instantly restore all five hearts so you can keep practicing.
$0.99 · one-timePick a sector
Master the English engineers actually use on the job.
Today's goal
0 / 50 XP
Category
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Lesson complete
XP earned
+0
Accuracy
0%
Out of Hearts
Practice paused. Refill your hearts in the Shop or unlock Voltlingo PRO for unlimited play.
Next heart in 30:00
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Sound effects
Ding on correct answers, buzz on misses, fanfare on lesson end.
Daily goal
XP target per day. Hit it to advance your streak.
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Voltlingo PRO
For engineers who want to learn faster. Unlock the full experience.
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