a walled town的用法和样例：
- At the fringe of recorded history, during the Western Zhou dynasty from about 1000 years before our era, there existed a walled town about 40 kms to the southwest.
- The old town on the hill had a wall right round it.
- A balcony is a platform with a wall.
- He crashed his car (into a wall).
- A continuous course of stones supporting a wall.