fathom
- v. 弄懂, 理解
- Definition
- v. to understand something after thinking about it carefully
- Example
- I simply cannot fathom why he quit such a great job.
- 我实在无法理解他为什么会辞掉这么好的工作。
Synonyms & Differences 近义词辨析
Compared meaning: understand something difficult completely (verb).
比较义项：想通，理解透彻（动词）。
- penetrate
Suggests seeing through something deliberately hidden or obscure, such as a secret, code, or disguise; formal and literary, common in phrases like 'penetrate the mystery'.
指看透某种被刻意隐藏或晦涩难懂的事物（秘密、密码或伪装）；语体正式、书面化，常见于“看穿谜团”这类说法。
The reporters never managed to penetrate the company's carefully guarded secrets.
记者们始终未能看穿这家公司严密保守的秘密。
- fathom 本词
More common and everyday; describes a personal struggle to understand something puzzling or someone's reasoning, often used with 'can't/couldn't' plus a 'why' or 'how' clause.
更常用、更口语化；通常表示个人难以理解某件令人费解的事情或某人的想法，常与“不能／无法”搭配，后接“为什么”或“怎么会”。
I really can't fathom why she turned down such a generous offer.
我实在弄不懂她为什么会拒绝这么慷慨的提议。
Both mean to fully understand something hard to grasp. Penetrate suggests seeing through something deliberately hidden, like a secret or code; it is formal and literary. Fathom is more common, describing a personal struggle to understand something puzzling, often with can't or couldn't.
这两个词都表示经过思考后想通、理解某件不易懂的事，但语体和常见搭配不同；这里不比较 penetrate“穿透，穿过（实体）”的义项。