Beijing ________ a lot in the past ten years. Now it has become one of the biggest modern ________ in the world.

1. A.
   changes; cities
2. B.
   changed; city
3. C.
   has changed; cities
4. D.
   had changed; cities

Beijing ______a lot in the past ten years. Now it has become one of the biggest modern______ in the world.

A. changes, cities    B. changed, city     C. changed, cities            D. has changed, cities

Beijing ________ a lot in the past ten years. Now it has become one of the biggest modern ________ in the world.

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Beijing ______a lot in the past ten years. Now it has become one of the biggest modern______ in the world.