6. The __________________ , stretching 21,196 meters, is the longest defending wall in the world.
举一反三
- 中国大学MOOC: 6. The __________________ , stretching 21,196 meters, is the longest defending wall in the world.
- The city wall of Pingyao Ancient City is 46 kilometers. It is about 10 meters high and 3 to 6 meters wide on top.
- The wall is about 9 meters high and 7.5 meters thick
- The wall is about 7.5 meters high and 9 meters _______. A: long B: deep C: thick
- The Mississippi River is the longest river in the world.