leading

Compared meaning: important or significant (adjective).

比较义项：主要的、重要的（形容词）。

• major

  Describes something as significant or important among several factors, without ranking it as the very top one; used broadly with problems, decisions, roles, injuries, or cities.

  表示某事物在多个因素中占重要地位，但不强调它是最顶尖的一个；常与问题、决定、角色、伤情、城市等搭配。

  Traffic congestion is a major problem in this city.

  交通拥堵是这座城市的一个主要问题。

• leading 本词

  Describes someone or something as foremost or top-ranked within a field, implying direct comparison with rivals; common with roles like leading actor, leading expert, leading company.

  表示某人或某事物在某个领域中处于最前列、领先于同行，隐含与竞争者的直接比较；常与“领衔演员”“领先专家”“领先公司”等搭配。

  She is the leading expert in cancer research.

  她是癌症研究领域的顶尖专家。

Major and leading both mean important, but they focus differently. Major describes something as significant among several factors, without ranking it the very top; used with problems, roles, or cities. Leading describes someone or something as first or best in a field, compared with rivals.

这两个词在“主要的”这个意义上容易混淆，但强调点不同：major 强调该事物在众多因素中占有重要地位，而 leading 强调在某个领域或排名中处于最前列、领先于其他同类。此处不比较 major 作名词表示“主修专业”或“少校”的用法。

Compared meaning: in front of others; first (adjective).

比较义项：领先的（形容词）。

• ahead

  Used predicatively, usually after 'be' or 'get', often followed by 'of' + a noun phrase, describing someone's position or progress relative to others; rarely placed before a noun in this sense.

  通常用作谓语（跟在be或get之后），常与“of＋名词短语”搭配，表示某人在位置或进度上领先于其他人；在这个意义上很少放在名词前作定语。

  After the first lap, she was already ahead of every other runner.

  跑完第一圈后，她已经领先于其他所有跑步者了。

• leading 本词

  Used attributively, directly before a noun, describing someone or something that ranks first or foremost within its field or category; not used with 'of' or as a predicate in this sense.

  通常用作定语，直接放在名词前面，表示某人或某事在其领域或类别中排名第一或最重要；在这个意义上不与of搭配，也不用作谓语。

  Dr. Chen is the leading expert in renewable energy research.

  陈博士是可再生能源研究领域的领先专家。

Ahead and leading both mean in front of others, but grammar differs. Ahead usually comes after be or get, often with of, describing someone's position or progress. Leading usually comes before a noun, describing someone or something that ranks first in a field.

这两个词都可以表示“领先的”，但用法不同：ahead通常用作谓语（跟在be或get之后），常与of连用，强调某人或某事在位置、进度上超过他人；leading通常放在名词前作定语，强调在某个领域或类别中排名第一或最重要。