Original sentence: The lyrebird sounds as good as the lyre, whose shape its tail resembles.
Better (clear and simple): The lyrebird sounds as good as a lyre, and its tail looks like a lyre.
Even simpler for a 6-year-old: The lyrebird sings like a lyre, and its tail looks like one.
Why this is better (easy steps):
- We use "a lyre" instead of "the lyre" because we mean any lyre, not one special lyre.
- "Whose shape its tail resembles" is a long and tricky phrase. It's easier to say "its tail looks like a lyre."
- We split the idea into two short sentences so it's easier to understand: one about the sound, one about the tail.
If you want to keep it as one sentence but simpler: The lyrebird sounds like a lyre and its tail is shaped like one.
Great job noticing that sentence — you're asking the right questions!