了解する · noun or participle which takes 'suru'
| Form | Positive | Negative |
|---|---|---|
| Dictionary | 了解する | 了解しない |
| Polite | 了解します | 了解しません |
| Past polite | 了解しました | 了解しませんでした |
| Past | 了解した | 了解しなかった |
| Te-form | 了解して | 了解しないで |
| Desire | 了解したい | 了解したくない |
| Potential | 了解できる | 了解できない |
| Passive | 了解される | 了解されない |
| Causative | 了解させる | 了解させない |
| Causative passive | 了解させられる | 了解させられない |
| Volitional | 了解しよう | |
| Polite volitional | 了解しましょう | |
| Imperative | 了解しろ | 了解するな |
| Conditional | 了解すれば | 了解しなければ |
| Tara conditional | 了解したら | 了解しなかったら |
noun, noun or participle which takes 'suru', transitive verb
comprehension; understanding; consent; agreement
Used for grasping a situation or giving consent. Often used in formal or business contexts to acknowledge information or agree to a plan.
彼の説明で状況を了解した。
I understood the situation from his explanation.
I got my boss's consent for the change of plan.
Interjection used as an acknowledgment, especially in radio communication or casual confirmation. Equivalent to 'roger' or 'copy that'.
"Roger, I'm on my way."
I replied 'roger' over the radio.
I changed the business trip schedule after getting my boss's approval.
"Let's meet at five." "Got it."
Both parties came to an understanding about the terms of the contract.
Before moving forward with the plan, I asked the stakeholders for their consent.
納得 stresses being convinced or satisfied by a reason, whereas 了解 simply means understanding or acknowledging information.
了解 is a casual, often workplace-slang way to acknowledge instructions, while 畏まりました is the highly polite, deferential version used in service settings.
了解 specifically signals that a message or instruction has been understood and accepted, while ＯＫ can also mean simple approval or acceptability of a state.
了解 often means acknowledging or confirming that one understands (as in giving consent or a go-ahead), while 理解 focuses on the mental process of comprehension itself.
Rarely used kanji form.