Whatever names they use, they all match the path expression based on their substitution group head element.

不管使用哪个名称，它们都匹配基于它们的代替组head元素的路径表达式。

youdao

Slightly smaller than the head of a match - the best implants today are only as small as a matchbox - the chip works by blocking pain signals on their way to the brain.

这种智能芯片比火柴头还稍小，而现今最好的植入物却仅仅是如火柴盒一样大小，这种芯片通过阻断传向大脑的疼痛信号来发挥作用。

youdao

There are plenty of derbies and rivalries in English football but none quite match the intensity, competitiveness and hatred borne out when Liverpool and Manchester United go head-to-head.

德比和宿敌的例子在英格兰足球里不胜枚举，但是当利物浦撞上曼联，那爆发出来的力量，对抗和怒火让所有其它比赛难以企及。

youdao

And: "All around, people looking half-dead, walking on the sidewalk, hotter than a match head."

VOA: special.2009.06.22

In a head-to-head match with Mr. Weiner, Ms. Quinn defeats him 48% to 33%.

WSJ: Anthony Weiner Joins the New York City Mayoral Debate

In March a Fox News Latino poll found that, in a head-to-head match-up, Mr Romney would carry just 14% of the Hispanic vote.

ECONOMIST: Immigration politics

And that's why, you know, every poll shows that I do better among independents than any other Democratic candidate and that I'm beating John McCain, because I actually attract more independents than he does in a head-to-head match-up.

NPR: Obama: Change Motivating Voters, Not Race