China's metro systems

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Across
  1. 3. Beijing and _____ have the world's longest metro systems.
  2. 5. a type of train that uses electromagnetic force
  3. 6. What city has China's oldest metro system?
Down
  1. 1. The world's oldest metro system is located in _____.
  2. 2. Shenzhen's metro system has _____ more lines than Hong Kong does.
  3. 4. Of the four metro systems mentioned in the paragraph, this city has the fewest daily passengers.