美国是世界上最发达的国家，的翻译：United States is the world's most developed countries, 什么意思？中文翻译英文，英文翻译中文，怎么说？

青云英语翻译

The United States is the world's most developed countries,

United States is the world's most developed countries,

US is in the world the most developed country,

The United States is the world's most developed countries.

United States is the world's most developed countries,