What You Can Do (られる・える)

弾く becomes 弾ける (く→け), 覚える becomes 覚えられる (drop る, add られる). The object of the original verb often switches from を to が in the potential form, ピアノを弾く becomes ピアノが弾ける, though を still works too in casual speech.

The passive form and the potential form of a る-verb look completely identical, 見られる can mean either “is seen” or “can see,” depending on context alone. う-verbs avoid this ambiguity entirely since their passive and potential forms are built differently, 飲まれる (passive) versus 飲める (potential).