In America, presidential elections are held every four years.

South America separated from Africa 200 million years ago.

2亿年前南美洲和非洲分离。

South America and Africa separated 200 million years ago.

南美洲和非洲于2亿年前分离。

Teenager Jake Denham was skiing with his family in the USA when he fell over and lost one of his skis.

十几岁的杰克·邓纳姆和他在美国的家人一起滑雪时摔倒了，并弄丢了一块滑雪板。

But it was in my home country, the USA, that I came closest to death.

但我最接近死亡的经历发生在我的祖国美国。

He's emigrated to the USA and gone completely native.

他已移居美国且完全成了美国人。

Results of USA WEEKEND's Teens& Parents survey reveal a generation of young people who get along well with their parents and approve of the way they're being raised.

《美国周末》“青少年与父母”版块的调查结果显示这代青少年与父母相处十分融洽，并且满意父母的培养方式。

After 15 years in the USA, he has finally decided to apply for American citizenship

在美国生活了15年之后，他终于决定申请美国国籍。

Greg went back home to the USA to raise money for the school.

格雷格回到美国为学校筹款。

Still, in my studies and others I have read, I find the same patterns as in USA WEEKEND'S survey.

但是在我的研究以及我读的别人的研究报告中，我得出了与《美国周末》相同的结论。

Only about 50 students are invited based on their performance on written tests and at the USA Math Olympiad.

只有大约50名学生能够获得邀请，遴选依据是笔试成绩和在美国数学奥林匹克比赛中的表现。

When this tradition travelled from West Africa to the USA, it developed into different musical styles.

当这个传统从西非传到美国时,它发展成了不同的音乐风格。

And in South America people usually stand quite close to each other when they talk, but in countries like the USA you need to give people more personal space.

在南美，人们说话时通常站得很近，但在美国这样的国家，人们需要更多的私人空间。

Usa is a cultural melange.

美国是个文化大熔炉。

A Legal Analysis of the USA Foreign Trade Law in Recent Years

晚近美国对外贸易政策的法律分析

That's a general British failing. In the USA it's quite different

那是英国人的普遍缺点。在美国，情况就大不一样了。

Comparative Study on Area of Water Source Management System between China and USA

中美水源地管理体系的比较研究

In the USA, those are often packed in brown paper bags.

因为在美国，午餐盒饭多半都装在棕色纸袋里。

USA can be written with dots or without.

写usa时，可以加点，也可以不加。

Analysis and Reference of Science and Technology Decision-making Mechanism of USA

对美国科技决策机制的分析与借鉴

Moreover, the USA has a track record of successfully accepting immigrants ．

此外,美国有成功接受移民的记录。