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An easy approach to the walls must be provided against: indeed they should be surrounded by uneven ground, and the roads leading to the gates should be winding and turn to the left from the gates.
必须有一条通往城墙的捷径:实际上，城墙应该被凹凸不平的地面包围，通往城门的道路应该蜿蜒曲折，从城门向左拐。