请问 the USA 和 the UK 在句子中什么时候加定冠词the 什么时候不加 谢谢啦

Question

Being a 20
century country,USA, was
full of
advantaged in
the world, nevertheless, at the same time also lost part of his pure and confidence of his youth age

Answer 1

在句子中任何时候都得加，拼开是 the United States of America 和 the United Kingdom

Answer 2

话说这两个都是专有词，不能不加the的吧

Answer 3

都是要加的。

Answer 4

都是专有名词，都需要加的

Answer 5

不管什么时候都必须加，不能不加。因为是国家专有名词