日本用英语怎么说

The question is "How to say Japan in English?"

In English, Japan is referred to as "Japan." There is no separate word for this country as it is already a recognized and established word in the English language. Therefore, to refer to Japan in English, simply write or speak "Japan." This term encompasses all aspects of Japanese culture, society, politics, economy, and more. It is a straightforward and widely used way to refer to this fascinating East Asian nation.