Translation guide
In Japanese, expressing speculation involves various grammatical patterns that convey degrees of certainty, inference, or hearsay. The most common and versatile is だろう／でしょう, used for conjecture. Other patterns like かもしれない express possibility, while らしい and みたい indicate hearsay or resemblance-based inference. The choice depends on the source of information and the speaker's confidence.
Express a personal guess or inference about a situation, often based on reasoning or intuition.
Plain form conjecture, used in casual speech or writing. Attaches to the plain form of verbs, adjectives, and nouns.
Polite form of だろう, used in formal speech or writing. Same conjecture meaning.
Literally 'I think that...', used to explicitly state personal speculation. Less direct than だろう.
I think it will rain tomorrow.
Indicate that something is possible but not certain.
Expresses possibility or uncertainty. Can be used for both positive and negative outcomes.
He might come.
Convey that information is based on what you heard from someone else or on observable evidence.
Express speculation in academic, journalistic, or formal writing.
Literally 'is seen as', used in news reports to indicate speculation or inference by observers.
だろう expresses a higher degree of certainty (probably), while かもしれない expresses a lower degree (might). Use だろう when you have some basis for your guess, and かもしれない when you are simply acknowledging a possibility.
He will probably come. (I'm fairly sure)
He probably won't come.
It might rain.
Casual abbreviation of かもしれない, common in spoken Japanese.
He might come.
I heard it will rain tomorrow.
Casual expression for 'seems like' based on direct observation or impression. Similar to ようだ but more colloquial.
It looks like he's not coming.
More formal/literary version of みたい, expressing inference from evidence.
It appears he's not coming.
Explicitly marks information as hearsay. Attaches to plain form. Note: different from the 'looks like' そうだ which attaches to verb stems.
I heard that he's not coming.
The economy is expected to recover.
Means 'it is thought that', used for objective speculation in formal writing.
The cause is thought to be a virus.
彼は来るかもしれない。（可能性がある）
He might come. (It's possible)
Both indicate hearsay, but らしい can also be used for inference based on evidence, while そうだ is purely for reporting what you heard. らしい is more indirect and can imply the speaker's own judgment.
It seems he's not coming. (Based on what I heard and my inference)
I heard he's not coming. (Just reporting what I heard)