city 一般指大城市或重要城市。
town 一般指规模小的城镇，也指城市中的市区，有时也泛指城市。
参考例句
1. Can the town be secured against attack ? 能保护这个市镇不受攻击吗?
2. The town has about a thousand inhabitants. 这个城镇大约有一千个居民。
3. This park is (the safest) park in our town. 这是我们镇上最安全的公园。
英英解释
n.
1. an urban area with a fixed boundary that is smaller than a city
2. an administrative division of a county
3. the people living in a municipality smaller than a city
