a
the letter A
Letter name · 字母名称the 1st letter of the English alphabet
英文字母 A（第 1 个字母）
Source: BridgeDict Latin alphabet catalog
穿过,横过。
先理解核心含义，再看它在真实句子里的用法。
穿过,横过。；(拉丁语)在...年
across
The noun sense means the letter itself. Scientific meanings appear only when their capitalization exactly matches your query.
the 1st letter of the English alphabet
英文字母 A（第 1 个字母）
Source: BridgeDict Latin alphabet catalog
the SI prefix atto, representing a factor of 10^-18
国际单位制词头 atto，表示 10^-18
Source: BIPM SI BrochurePrepare the learner guide for this word
可生成：语法 Grammar、学习解释 Learner guide、例句 Examples。只有点击后才会开始生成。
穿过,横过。
across
(拉丁语)在...年
annō (Latin for “in the year”)
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该词属于 Oxford 核心词汇，值得优先掌握常见搭配和句型。
Collins 词频等级为 5，建议结合例句记忆，而不是只背中文释义。
页面下方列出了常见词形变化。学习时注意它们在句子中的语法位置。
Dictionary facts from AI_FALLBACK, ECDICT, WIKTIONARY, BridgeDict Latin alphabet catalog, BIPM SI Brochure.