英文破折号在文中主要起到解释说明和强调等作用,同时,它还可以在一些情况下代替逗号、括号以及冒号,增强文本的可读性。我们所讨论的英文破折号在英语中称为Em dash(—),除此之外还有连接号En dash (–),它的长度是 Em dash 的一半,主要用于连接数字表示起止范围(比如1:00–2:00 ),以及表示两者之间的关系和联系(比如 Boston–Hartford route)。另外,还有连字号Hyphen (-),它的长度比En dash还要短,主要用于行末单词换行以及连接复合词的各个组成部分(比如 20-year-old son)。英文破折号都有哪些作用?具体来讲,英文破折号有以下几个功能:(1)对上文内容进行解释说明破折号最常见的用法是对上文进行补充说明,使读者对上文有更多了解。比如《经济学人》最近的一篇文章里面有这样一句话:Real estate is the biggest asset market in the The value of residential property in America—at around $34trn—rivals the market capitalisation of all listed American 这里作者使用破折号对美国居民住宅总价值进行了说明——大约34万亿美元。又比如:The first law of motion—every object in motion will stay in motion until acted upon by an outside force—explains why a ball dropped from the top of a roof will not stop in mid-air but will continue to fall until it hits the 两个破折号中间的内容every object in motion will stay in motion until acted upon by an outside force对牛顿第一定律进行了解释。(2)对内容进行强调写作中作者经常用破折号对某些单词、句子和语义内容加以强调,使之重点突出,引起读者的注意。比如我们在之前的外刊精读文章中出现了这样一个标题:英文破折号都有哪些作用?Britain’s fisherfolk fret about being sold down the river—yet again作者在这里用破折号来强调英国渔民担心再一次被政府出卖。又比如:Many employees—mostly recent graduates with student loans—must ride the bus to 作者用破折号对mostly recent graduates with student loans这一部分信息进行突出。写作中我们可以使用圆括号(parentheses)来对句子内容进行强调,比如:Upon discovering the errors (all 124 of them), the publisher immediately recalled the 如果我们需要进一步强调内容,可以改用破折号,因为破折号更明显,给人的感觉更直观,例如:Upon discovering the errors—all 124 of them—the publisher immediately recalled the 这样更加突出"all 124 of them"这一信息。(3)归纳概括作者在列举一些事物后有时候会用破折号对前面的内容进行归纳概括,进而叙述自己的看法或结论,这样能使行文更加紧凑。比如:Male and female, old and young, short and tall—people of all shapes and sizes can participate in activities at the community 这里破折号后面people of all shapes and sizes对前面列举的几个人物特点进行总结。又比如:Reliability, trustworthiness, diligence—this company only hires employees with all of these 作者在开头先列举出三个品质:可靠、可信赖和勤奋,接下来解释说明这些品质是公司招人时着重的点。这里破折号的使用能够制造悬念,增强句子的可读性。(4)代替逗号以及冒号当英文中出现并列成分时我们会用逗号将并列成分分开,但有时候只用逗号可能会使版面不美观,比如:My cousins, Oliver, Harry, and Lyra, cannot attend my birthday The teacher wrote the titles of the books, The Golden Compass, The Subtle Knife, and The Amber Spyglass, on the 在这种情况下可以使用破折号来代替,比如上面句子可以改为:My cousins—Oliver, Harry, and Lyra—cannot attend my birthday The teacher wrote the titles of the books—The Golden Compass, The Subtle Knife, and The Amber Spyglass—on the 破折号在一些情况下也可以代替冒号用于强调,比如:After months of deliberation, the jurors reached a unanimous verdict: After months of deliberation, the jurors reached a unanimous verdict—英文破折号除了上面这几个用法之外,还可以在文学作品中表示语气的中断或转折,以及字句的省略等等,各位同学在日常阅读中可以多加留意体会。