打不開這件事（狀態）
這一支就是核心本身：把「做不到」當成一個抽象的狀態來談。
being impossible · noun · C2
The fact that something cannot happen or cannot be done, no matter how hard you try.
不可能
核心畫面
One way to picture it: a door that has no handle on either side. It is not that you have not pushed hard enough — the pushing itself leads nowhere, because there is nothing there that can open. `impossibility` is the name for that closedness itself.
一扇沒有把手的門。重點不是你力氣不夠、還沒用力推——而是這扇門本身就沒有可以開的地方，再怎麼推也只是推在牆上。imp…更多收起
一扇沒有把手的門。重點不是你力氣不夠、還沒用力推——而是這扇門本身就沒有可以開的地方，再怎麼推也只是推在牆上。impossibility 這個字指的就是「這件事打不開」這個狀態本身；它是抽象名詞，講的是那份「做不到」，而不是講哪一件事做不到。From the word’s history
From Latin impossibilitās, built on impossibilis (im- 'not' + possibilis 'able to be done'), which comes from posse 'to be able'. So the word literally names the absence of the can: not-able-ness.
來自拉丁文 impossibilitās，底層是 impossibilis：im-（不）＋ possibilis（做得到的），而 possibilis 又來自 posse（能夠、有能力）。所以這個字從字面上就是在替「沒有那個『能』」命名——不是「難」，是「能力這件事根本不存在」。這也解釋了為什麼中文常常要用「不可能」而不是「很難」來翻它。
Wiktionary, 'impossibility' / 'impossible' (from Middle French impossibilité, from Latin impossibilitās; im- + possibilitās, ultimately from posse 'to be able')
Three branches
打不開的那個東西（具體所指）
從「這個狀態」轉成「帶有這個狀態的那樣東西」——抽象名詞落地成一個可以用手指出來、可以數的東西。
an impossible thing · noun · C2
Something that cannot be done or cannot happen; a thing you can point to as out of reach.
不可能的事
人或要求讓人受不了
把「打不開」從物理／邏輯搬到人際上：不是宇宙定律說不行，是這個要求或這個人讓別人沒辦法配合下去。
unreasonable demand · noun · C2
Something you cannot reasonably ask, because the demand is too much or a person's behaviour is too hard to live or work with.
強人所難
原始詞典資料3 筆記錄
以下是外部詞典記錄的用法，原文照列，我們還沒有寫成教學內容。上面的說明才是我們自己寫的；有些用法可能上面已經講過了。
impossibilitynoun/ɪmˌpɒsɪˈbɪliti/
- 1
Something that is impossible.
- Meeting the deadline is an impossibility; there is no way we can be ready in time.
- God commands not impossibilities; and all the Ecclesiastical glue, that Liturgy, or Laymen can compound, is not able to soder up two such incongruous natures into the one flesh of a true beseeming Mariage.
- 2
The quality of being impossible.
- 1548, Edward Hall, The Union of the Two Noble and Illustre Families of Lancastre and Yorke, London: Richard Grafton, Henry VIII, year 15, After long reasonyng, there wer certain appoynted, to declare the impossibilite of this demaunde to the Cardinal,
- [L]et the mutinous winds / Strike the proud cedars ’gainst the fiery sun; / Murdering impossibility, to make / What cannot be, slight work.
- 3
obsoleteThe state of being unable to do something.
- Here by this petition whan we say, Leade vs not into temptation, we learne to know our own impossibilitie and infirmitie, namely that we bee not able of our owne selues to with∣stand this great and mightye enemye the deuill.
- […] out of their own torment, they [the damned] see the felicitie of the saints; togither with their impossibility of attayning it.
資料來源：英文維基詞典 English Wiktionary（CC BY-SA 4.0）。 原文照列，未經改寫。