～だろう

The ～だろう structure is used to express an assumption, probability, or guess in a casual or neutral tone. It is the less formal counterpart of ～でしょう and is often used in written texts, monologues, or conversations among peers.

• Expressing Probability: Indicates that something is likely or probable based on reasoning or context, often in an informal setting.

  あす明日はあめがふる雨が降るだろう。

  It will probably rain tomorrow.

• Seeking Agreement: When spoken with a rising intonation, ～だろう can imply seeking confirmation or agreement, similar to "right?" or "isn't it?" in English. This is more common in casual speech.

• Softened Statements: Used in written or spoken language to soften definitive statements.
  このけってい決定はただしい正しいだろう。

  This decision is probably correct.

Comparison with ～でしょう

• ～でしょう is more polite and used in formal contexts, while ～だろう is informal or neutral.
• ～だろう is more commonly used by men in casual speech, while ～でしょう is more universal.