Complex sentence: Tone occurs both lexically (as a property of the word), non-lexically (as a result of tonological processes), and also as a marker of certain morphological features; for instance, the past tense marker is associated with high tone.
Split into simpler sentences: Tone occurs both lexically (as a property of the word), non-lexically (as a result of tonological processes), and also as a marker of certain morphological features. For instance, the past tense marker is associated with high tone.