A
The Union Jack is the national flag of the United Kingdom. It is so called because it combines the emblems (象征) of three countries—England, Scotland and Ireland (although since 1921 only Northern Ireland has been part of the United Kingdom)．
The term “Union Jack” possibly dates from Queen Anne's time, but its origin is uncertain. It may come from the “Jacket” of the English or Scottish soldiers; or from the name of James I who originated the first union in 1603, in either its Latin or French form “Jacobus” or “Jacques”； or, as “jack” once meant small, the name may come from a royal proclamation (声明) issued by Charles Ⅱ that the flag should be flown only by ships of the Royal Navy as a jack, a small flag at the bowsprit (船首)．
The Union Jack was originally a royal flag (when the present design was made official in 1801, it was ordered to be flown on all the King's forts and castles, but not elsewhere); it is today flown above Buckingham Palace and Windsor Castle when the Queen is not in residence. On news of a royal death, the Union Jack will be flown at half－mast (下半旗)．
The flying of the Union Jack on public buildings is decided by the Department for Culture, Media and Sport at the Queen's command. The Union Jack is flown on government buildings on days marking the birthdays of members of the royal family, such as the Queen's official birthday, and on the days of the State Opening and prorogation (休会) of Parliament; it is also flown on St David's Day, St George's Day, St Andrew's Day, and St Patrick's Day.
Although the Union Jack originated as a royal flag，it is now also flown by many people and organizations elsewhere in the United Kingdom. Its use as an emblem has extended beyond the form of a flag and the Union Jack is frequently shown on other objects.
文章大意：本文是一篇说明文。分析了英国国旗the Union Jack的起源和使用场合。
21．The reason why the national flag of the United Kingdom is called the Union Jack is that B.
A．the flag is made of jacket
B．the flag combines the emblems of three countries
C．the flag shows the symbol of unity
D．the flag originated from the existence of the United Kingdom
解析：细节理解题。第一段说到the Union Jack是三个国家象征的徽记集合。
22．The second paragraph mainly talks about A.
A．the origin of the national flag
B．the history of the national flag
C．the reason why the Union Jack has become the national flag
D．the way how the Union Jack has become the national flag
解析：主旨大意题。第二段的第一句为本段主题句。即讲述the Union Jack的起源。
23．What is the best title of the passage？C
A．The Union Jack Everywhere
B．The Union Jack Anytime
C．National Flag, the Union Jack
D．The History of the Union Jack
解析：标题判断题。A、B、D三项文章均有说到，但属于以偏概全，C项概括了文章的内容。故选C。
