auxiliary N3 common casualpolitewritten

〜込む — to do ~ thoroughly / repeatedly, or to move ~ inward

〜込む・こむ

Meaning

① inward: ~ into / ~ in — the action moves something or someone into an enclosed space

② thoroughly: ~ deeply / ~ intently / ~ for a long time — the action is done with sustained intensity

① inward

急いそいで電車でんしゃに乗のり込こんだ。

I rushed and got onto the train.

② thoroughly

彼かれは腕組うでぐみをして考かんがえ込こんだ。

He folded his arms and sank into deep thought.

Attaches to	Form	Example
Verb (masu-stem)	V(stem) + 込こむ	入はいる → 入はいり込こむ / 使つかう → 使つかい込こむ / 申もうす → 申もうし込こむ

① inward

子供こどもたちがプールに飛とび込こんだ。

The children jumped into the pool.

かばんに荷物にもつを詰つめ込こんだ。

I crammed my things into the bag.

② thoroughly

友達ともだちと夜遅よるおそくまで話はなし込こんでしまった。

I ended up talking with my friend deep into the night.

新人しんじんに仕事しごとを教おしえ込こむ。

I drill the work thoroughly into the new hire.

Many 〜込こむ compounds are fixed vocabulary worth learning whole: 申もうし込こむ ('apply'), 落おち込こむ ('feel down'), 黙だまり込こむ ('fall silent'), 思おもい込こむ ('be convinced').

Jengo shows 〜込む the way you actually meet it: inside real Japanese sentences, so it sticks instead of staying an abstract rule.

Sources Compiled from published Japanese grammar references.