"Playing on the street is dangerous" 是表达这个意思的常用短语。
这个短语的来源是因为在街上玩会有很多危险因素，如交通，空气污染等。
例句1: "It's not safe to play on the street, there's too much traffic" (在街上玩不安全，因为交通太多)
例句2: "Playing on the street can be dangerous because of the pollution" (在街上玩可能危险，因为污染)
例句3: "It's not a good idea to play on the street, it's much safer to play in a park." (在街上玩不是个好主意，在公园里玩更安全)