Impossible to understand, no matter how hard you think about it — so deep or so strange that your mind cannot reach the bottom.

Impossible to understand不可能理解，no matter how hard you think about it不管你想得多用力——so deep or so strange that your mind cannot reach the bottom深奧或奇怪到你的腦袋摸不到底。

A fathom was a measure of depth for water (about 1.8 metres), and to fathom water was to drop a weighted rope and find out how deep it was. So something unfathomable is water where the rope never touches bottom.

A fathom英尋（fathom） was a measure of depth for water以前是量水深的單位（about 1.8 metres大約1.8公尺），and to fathom water而測水深的動作 was to drop a weighted rope and find out how deep it was就是丟下一條綁著重物的繩子，看水有多深。So所以 something unfathomable某個 unfathomable 的東西 is water where the rope never touches bottom就是繩子永遠碰不到底的水。

That picture still lives inside the word, and it is why unfathomable feels bigger than "confusing." You use it for two rather different things.

That picture still lives inside the word這個畫面仍然活在這個字裡面，and it is why它就是為什麼 unfathomable feels bigger than 'confusing'unfathomable 給人的感覺比 confusing（令人困惑）更強烈。You use it for two rather different things你會用它來形容兩種相當不同的東西。

First, for what is genuinely beyond human understanding — the size of the universe, the mind of God, the depth of someone's grief. Here the word is respectful, even awed.

First首先，for what is genuinely beyond human understanding用在真正超出人類理解範圍的東西——the size of the universe宇宙的大小, the mind of God神的心思, the depth of someone's grief一個人悲傷的深度。Here在這種用法裡 the word is respectful, even awed這個字是帶著敬意，甚至敬畏的。

Second, and much more commonly today, for a decision so stupid you cannot see how anyone made it: "an unfathomable choice," "for reasons unfathomable to me." Here it is dry and a bit sarcastic.

Second其次，and much more commonly today而且現在更常見的用法，for a decision so stupid you cannot see how anyone made it是用在蠢到讓人搞不懂怎麼會有人這樣做的決定上：'an unfathomable choice,''令人費解的選擇'，'for reasons unfathomable to me.''基於我搞不懂的理由'。Here在這裡 it is dry and a bit sarcastic這個字是乾巴巴、帶點諷刺的。

English speakers also use it about people who hide their feelings well — an unfathomable expression, a face you cannot read. Note that it does NOT mean "very deep water" in the plain physical sense; you would not say an unfathomable swimming pool.

English speakers also use it about people who hide their feelings well英語使用者也會用它來形容很會隱藏情緒的人——an unfathomable expression一種讓人看不透的表情, a face you cannot read一張你讀不懂的臉。Note that請注意 it does NOT mean 'very deep water' in the plain physical sense它並不是單純字面上「很深的水」的意思；you would not say你不會說 an unfathomable swimming pool一座 unfathomable 的游泳池。