碰到心裡
這一支把「碰」從身體移到感覺上。東西沒有真的碰到你，但你心裡確實動了一下。
adjective · B2
Making you feel something soft inside — pity, sympathy, sadness, or warmth — usually because of kindness, love, or loyalty that you can see in what someone did.
動人的／感人的
核心畫面
You can think of touching as touch caught in the act: something is reaching out and making contact. In one direction the contact is with your feelings — a small kindness brushes your heart and you go quiet. In the other, the contact is with a subject — a letter or a rule reaches out and lands on a topic, so it is 'touching' that matter. Same reaching movement, different thing being reached.
touching 可以想成 touch 正在發生的樣子：有東西伸過來，碰到了。往一邊走，碰到的是你的感覺——一個小小…更多收起
touching 可以想成 touch 正在發生的樣子：有東西伸過來，碰到了。往一邊走，碰到的是你的感覺——一個小小的舉動輕輕碰了一下你的心，你就安靜下來了。往另一邊走，碰到的是一個題目——一封信、一條規定伸過去，落在某件事上，所以是「關於」那件事。伸手去碰的動作一樣，只是被碰到的東西不同。這樣看，兩個差很遠的用法就串在一起了。From the word’s history
Wiktionary gives touching as Middle English touchynge, that is touch + -ing. The modern uses all keep the picture of contact that the base verb carries.
來源說 touching 來自中古英文 touchynge，也就是 touch 加上 -ing。今天的各種用法，字面上都還留著 touch 那個「碰」的畫面。
Wiktionary, entry "touching" (kaikki snapshot kaikki:3f6f69a190036ae4:909516514): "From Middle English touchynge, equivalent to touch + -ing."
Two branches
碰到題目
同樣是伸手去碰，只是伸過去的是一份文件或一段話，碰到的是一個主題。碰到哪裡，就是在談哪件事。
preposition · C1
About; on the subject of. It comes before a noun and shows what matter is being dealt with, and it belongs to formal writing.
關於
原始詞典資料6 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。
touchingadj詞源 1/ˈtʌt͡ʃɪŋ/
- 1
Provoking sadness and pity; that can cause sadness or heartbreak among witnesses to a sad event or situation.
- a touching story
- 2
In direct contact with.
touchingprep詞源 1/ˈtʌt͡ʃɪŋ/
- 1
Regarding; concerning.
- Now as touching things offered vnto idoles, wee know that wee all haue knowledge.
- Every time I ascended to the deck from my watches below, I instantly gazed aft to mark if any strange face were visible ; for my first vague disquietude touching the unknown captain, now in the seclusion of the sea, became almost a perturbation.
touchingnoun詞源 2/ˈtʌt͡ʃɪŋ/
- 1
The act by which something is touched.
- But we can also take a more analytical attitude to these displays, interpreting the movements as no more than approachings, touchings, and departings with no implication that one shape caused the other to move.
- 2
A snack served with alcoholic drinks in an informal environment.
這個拼法也被記錄為下列字的變化形：
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。