一串又輕又快的聲音
這一組就是核心畫面本身，只是換了詞性：一個把那串聲音當成東西來講，一個把它當成動作來講。
noun · B2
The light, quick, quiet sound made by something small hitting a surface again and again, such as rain on a window or small feet running on a floor.
啪嗒聲
這個拼法底下其實是2個不同的字，意思沒有關係， 只是長得一樣。下面分開列出來。跳到 啪嗒聲 · 話術（順口的一套說詞）
1
patter
n, v核心畫面
Think of one raindrop hitting a window: a tiny tap. Then another, and another, faster and faster. Each sound is far too small to notice on its own, but together they make a light, quick, repeating run of taps that you cannot miss. That run of taps is what patter holds — rain on glass, bare feet crossing a wooden floor, a small dog's in the kitchen. Nothing in the picture is heavy. The noun names the run of sounds; the verb names the thing making them.
可以想成：一顆小雨滴打在窗玻璃上，啪。然後第二顆、第三顆，一顆接一顆，越來越密。每一下都很輕，輕到單獨一下幾乎聽不見…更多收起
可以想成：一顆小雨滴打在窗玻璃上，啪。然後第二顆、第三顆，一顆接一顆，越來越密。每一下都很輕，輕到單獨一下幾乎聽不見；但是連成一串，你就一定會注意到。patter 想抓住的就是這種聲音——小、快、一再重複、沒有重量。小孩光腳跑過木地板、小狗的爪子踩過廚房，聽起來都是同一個畫面。名詞講的是這一串聲音本身，動詞講的是「發出這一串聲音」這件事。From the word’s history
Wiktionary records this patter as pat (one light tap) plus the frequentative ending -er, first seen around the 1610s, and describes the word as imitating the sound itself. One light tap is pat; tapping again and again is patter.
字典記載這個 patter 是 pat（輕拍一下）加上表示「一再重複」的字尾 -er，大約 1610 年代出現，而且本身就是模仿聲音造出來的字。拍一下叫 pat，一直拍不停就成了 patter——這條線索跟今天的用法完全對得上。
Wiktionary, patter etymology 1 (source_ref kaikki:3f6f69a190036ae4:1172242367): "1610s, pat + -er (frequentative), of onomatopoeia origin"
Two branches
借這個聲音來說「家裡要有小孩了」
核心畫面裡本來就有一種聲音是小孩跑步的腳步聲。英文把這個聲音整個拿來當暗號：聽到小腳丫的聲音，就表示家裡多了一個小孩。
noun · C1
A joking way of talking about a baby coming into a family: if people ask about the patter of tiny feet, they are asking whether someone is going to have a baby.
要有小寶寶了（玩笑說法）
A second word, same spelling
2
patter
n, v核心畫面
Picture a market seller who has said the same words every night for ten years. He does not think about them any more. They come out fast, smooth, with a joke in the same place each time and no gaps anywhere. The talk is ready-made and it runs by itself. That ready-made, non-stop run of words is this patter — a seller's, a show host's, a magician's. It is not a claim that the speaker is lying; it is a claim that the words were prepared long before you walked up.
可以想成一個夜市攤販，同一套話他已經講了十年。他不用再想了。話一出口就又快又順，笑話每次都掉在同一個位置，中間一點空…更多收起
可以想成一個夜市攤販，同一套話他已經講了十年。他不用再想了。話一出口就又快又順，笑話每次都掉在同一個位置，中間一點空隙也沒有。這一整套現成的、自己會跑的話，就是這個 patter——攤販的、主持人的、魔術師的。它不等於在騙人。它說的是：這些話在你走過來之前就準備好了。也因為太順，聽的人會覺得好玩，但心裡通常會留一點距離。From the word’s history
Wiktionary treats this as a separate word from the sound one: the noun is attested in 1758, first used of the cant of thieves and beggars, and the verb comes from Middle English pateren, which meant to rattle through the Lord's Prayer. Words said so often that they run by themselves is the thread you can still hear in sales patter.
字典把這個 patter 當成跟「雨聲」那個完全不同的字：名詞大約 1758 年出現，最早指小偷和乞丐之間的黑話；動詞來自中古英語 pateren，早期指「快速地把主禱文念過去」。念到滾瓜爛熟、不用想就一路念完——這條線索今天還留在 sales patter 裡面。
Wiktionary, patter etymology 2 (source_ref kaikki:3f6f69a190036ae4:1172255956): "Noun is from Middle English pater, verb is from Middle English pateren. Noun attested 1758, originally referring to the cant of thieves and beggers."
From the picture
練熟的一套話
這一家就是核心畫面本身，一個當名詞（那套話），一個當動詞（正在講那套話）。
noun · C1
Fast, smooth, non-stop talk that someone uses to entertain people or to sell them something — the kind a market seller, a comedian or a show host has ready.
話術（順口的一套說詞）
Also in this word
verb · C1
To talk quickly and smoothly without stopping, the way a seller, an auctioneer or a show host does.
講得又快又順