整個沒進液體裡
這就是核心畫面本身，字面的用法。
verb · B2
To put a person or a thing all the way into a liquid, so that it is completely covered.
浸入
核心畫面
One way to hold this word: something goes under the water and the water closes over it. Not a splash, not a dipped corner, not a wet surface. The liquid touches every side at once, and from inside there is nothing else to touch. English then takes that same picture and puts a person's attention where the object was: a language, a book, a game surrounds you the way water does, and what is outside it stops reaching you.
可以想成：一個東西沉到水面下，水從上面合起來。不是潑到，不是沾一個角，也不是表面弄濕。液體同時碰到每一面，從裡面看出…更多收起
可以想成：一個東西沉到水面下，水從上面合起來。不是潑到，不是沾一個角，也不是表面弄濕。液體同時碰到每一面，從裡面看出去，只剩那些水。英文把同一個畫面搬到注意力上：一種語言、一本書、一款遊戲像水一樣把你圍住，外面的事就碰不到你了。所以這個字從頭到尾都在講同一件事——整個沒進去，沒有一角露在外面。From the word’s history
Wiktionary gives Latin immersus, from immergo, from in plus mergo, the same root that shows up in English merge and submerge.
Wiktionary 記的是拉丁文 immersus，來自 immergō，由 in 加 mergō 組成。mergō 這條線也長出英文的 merge 和 submerge，三個字裡都藏著同一個「沒進去」的動作。
Wiktionary entry for immerse supplied in packet (kaikki:3f6f69a190036ae4:647381939:21440)
Two branches
注意力整個沒進去
水換成一件事、一種語言、一個故事；被蓋住的不是身體，是注意力。外面的聲音一樣進不來。
verb · B2
To make someone become completely involved in something, so that their attention is fully inside it. It is often used in the passive: if you are immersed in a book, the room around you falls away.
使沉浸其中