形容詞：把分開的收成一個
這是原本的用法：先有「合起來」這個描述，才有後面被合起來的那些機器。
adjective · B1
Bringing two or more things that usually come separately together inside one product, one machine or one price, so that you only need to get the one thing.
多合一的
核心畫面
One way to picture all-in-one: things that normally sit in separate boxes, gathered into a single box. A printer, a scanner and a copier become one machine; a screen and a computer become one machine; a room, a breakfast and a bus ride become one price. The word is really a whole phrase — all in one — tied together with so it can work as a single word.
all-in-one 可以想成把本來各自一盒的東西，收進同一個盒子裡。印表機、掃描器、影印機變成一台；螢幕和主機變成…更多收起
all-in-one 可以想成把本來各自一盒的東西，收進同一個盒子裡。印表機、掃描器、影印機變成一台；螢幕和主機變成一台；房間、早餐、接送變成一個價錢。它其實是一整句話 all in one（全部在一個裡面），用連字號綁起來當一個字用。所以它既能拿來形容東西，也能直接拿來指那台被合起來的機器。Two branches
名詞：那台合起來的機器
形容詞用久了，後面的名詞被省掉，整個詞就直接拿來指那台機器。兩個名詞意思的差別，只在於被合起來的是什麼。
noun · B2
A machine that does on its own the jobs of several separate machines — most often a printer that also scans, copies and sometimes sends faxes.
多功能事務機