舊胎換上新的一層
這一支就是核心畫面本身，名詞是那條胎，動詞是把新面黏上去的那道工。
noun · C1
An old tire that has had a new rubber surface put on it, so that it can be driven on again instead of being thrown away. British spelling: tyre.
再生輪胎
核心畫面
Picture a truck tire that has been driven flat. The body of it is still strong; only the grooved face that meets the road has worn smooth. So that face is stripped off and a new layer of rubber is bonded on, and the tire rolls out of the workshop looking new. That is the picture the word keeps returning to: an old thing with a fresh surface. Most of what retread does in English is that picture applied to something else — a story given a new title, a worker given new skills. One branch is separate: it is built on tread meaning to walk, and it means going over the same ground a second time.
可以先想一條跑到胎面磨平的卡車輪胎。骨架其實還很硬。磨掉的只有那層壓在路上、有溝的橡膠。於是把那一層刮掉，再黏上一層…更多收起
可以先想一條跑到胎面磨平的卡車輪胎。骨架其實還很硬。磨掉的只有那層壓在路上、有溝的橡膠。於是把那一層刮掉，再黏上一層新的。輪胎推出工廠時，看起來就像新的。這個字大部分的用法都繞著這個畫面轉：舊的底、新的面。把畫面套到別的東西上，就長出其他意思——一個故事換個片名再上一次，一個人換一套本事再上工。只有一支不走這條線：它接的是 tread「走路」的意思，講的是同一條路再走一遍。From the word’s history
Wiktionary gives two entries. One is re- plus tread meaning the grooves carved into the face of a tire; the other is re- plus the verb tread, meaning to walk.
Wiktionary 把這個字分成兩個字源。一個是 re- 加上名詞 tread（輪胎表面刻出來的溝紋），輪胎和它的各種比喻都從這裡來。另一個是 re- 加上動詞 tread（踩、走），「再走一次」那一支從這裡來。兩支同拼法，連過去式都不一樣。
Wiktionary entries for retread, etymologies 1 and 2: From re- + tread (grooves carved into the face of a tire, noun) / From re- + tread (verb). Source refs kaikki:3f6f69a190036ae4:1098815069:5490 and kaikki:3f6f69a190036ae4:1098827607:3773
Two branches
底子沒換，只換了外面那一層
把輪胎的畫面直接套到不是輪胎的東西上。重點不在「再一次」，而在「換的只有表面」。
noun · C2
Something — usually a film, show, book or plan — that is an earlier one done again with only small changes. The source marks it informal and says it shows disapproval: calling something a retread says you think there is nothing new inside it.
老調重彈的東西