미국은

미국은

"미국은" means "As for the U.S." or "The U.S. (topic marker)."

In this sentence, '미국은' serves as the subject, emphasizing the features of the United States being described.

미국은 넓은 땅과 풍부한 자원을 가지고 있습니다.

The United States has vast land and abundant resources.

Here, '미국은' is used as the subject of the sentence, meaning 'The United States', introducing the topic being discussed.

미국은 다양한 문화가 공존하는 나라입니다.

The United States is a country where various cultures coexist.

Here, '미국은' highlights the United States as the actor that contributed to the development of democracy.

미국은 민주주의의 발달에 중요한 역할을 했습니다.

The United States has played an important role in the development of democracy.