思い込む · godan verb (-mu)
| Form | Positive | Negative |
|---|---|---|
| Dictionary | 思い込む | 思い込まない |
| Polite | 思い込みます | 思い込みません |
| Past polite | 思い込みました | 思い込みませんでした |
| Past | 思い込んだ | 思い込まなかった |
| Te-form | 思い込んで | 思い込まないで |
| Desire | 思い込みたい | 思い込みたくない |
| Potential | 思い込める | 思い込めない |
| Passive | 思い込まれる | 思い込まれない |
| Causative | 思い込ませる | 思い込ませない |
| Causative passive | 思い込ませられるalso 思い込まされる | 思い込ませられないalso 思い込まされない |
| Volitional | 思い込もう | |
| Polite volitional | 思い込みましょう | |
| Imperative | 思い込め | 思い込むな |
| Conditional | 思い込めば | 思い込まなければ |
| Tara conditional | 思い込んだら | 思い込まなかったら |
godan verb (-mu), intransitive verb
be convinced; be under the impression; assume
Used when someone firmly believes something, often with と or と思い込む. It commonly implies the belief may be mistaken or too strong.
He is convinced that he is right.
I was under the impression that the train left at ten.
godan verb (-mu), intransitive verb
make up one's mind; set one's heart on; be determined
Focuses on a firm personal resolve or fixed intention. Often appears in patterns like 一度思い込んだら, meaning that once someone has set their mind on something, they are hard to stop.
Once he sets his mind on something, he sees it through to the end.
She set her heart on working overseas and started studying English.
godan verb (-mu), intransitive verb
be obsessed with an idea; fixate on; think about obsessively
Describes getting mentally stuck on one idea, worry, suspicion, or interpretation so strongly that it becomes hard to see anything else.
If you fixate on the negative interpretation, you become more and more anxious.
When he gets obsessed with one idea, he stops hearing what people around him say.
He is convinced that he's right.
Once he gets an idea like that into his head, he rarely changes his mind.
She just assumed, without basis, that he was angry.
He made everyone believe that he was a genius.
思い込む means to become convinced of something (often mistakenly), while 思い上がる specifically means to become conceited about oneself; learners confuse them because both start with 思い.