One way to hold this word: two oxen under a single yoke. They are two, they stay two, and yet they can only move together. Every use of conjugate keeps that picture. Verb forms are yoked into one set. A number and its conjugate are yoked into one pair. Two molecules are yoked into one new thing. Two cells are yoked together just long enough to pass something across.
可以想成兩頭牛套在同一根軛上。牠們是兩個，還是兩個，但只能一起走。conjugate 的每個用法都留著這個畫面。動詞的各種形式被綁成一組。一個數和它的共軛綁成一對。兩個分子被接成一個新東西。兩個細胞暫時搭在一起，把遺傳物質送過去。中文的「共軛」用的正是同一個軛字，這條線對得非常準。
From the word’s history
From Latin coniugo, con- (with) + iugo (to join, to yoke), literally to yoke together.
來自拉丁文 coniugō：con-（一起）加上 iugō（連結、套軛），字面就是「套在同一根軛上」。所以上面的畫面不只是記憶用的比喻，這個字本來就是這樣造出來的。
Wiktionary entry for conjugate, etymology supplied in this packet (kaikki:3f6f69a190036ae4:470423272)
登入就可以看每一支怎麼連回核心畫面。