英文中的三个横线符号hyphen, en dash和em dash

英文中有三个符号
‐
–
—
依次称为hyphen、en dash、em dash，长度由左向右递增。
1. hyphen, 连字符
Unicode编码 2010, ASCII编码 0045
用法:
连接前后缀,
连接单词构成复合词,
分隔数字,
排版时的行尾断词等,
Anti-war
upper-case
400‐820‐820
My name is Phyllis; that's p-h-y-l-l-i-s.

2. en dash, 连接号
Unicode编码 2013, ASCII编码 0150
用法:
连接数据表示起止范围,
表示两者之间的关系或联系,
在复合型形容词中替代hyphen,
后边什么也不接
Her college years, 1998–2002, were the happiest in her life.
New York–London route
the post–World War II years
Donald Trump(1946–)

3. em dash, 破折号
Unicode编码 2014, ASCII编码 0151
用法:
替代逗号将句子中的某个成份分离出来,
分隔句子中插入的想法或从句
表示断断续续
The influence of three impressionists—Monet, Sisley, and Degas—is obvious in her work.
Consensus—that was the will-o’-the wisp he doggedly pursued.
"Will he—can he—obtain the necessary signatures?" asked Mill.