〜一方

On one hand...; On the other hand...; Continuously...

1. Overview

「〜一方」has multiple uses, primarily for contrasting two things or describing a unidirectional trend. Depending on the context, it can be translated as “on one hand… on the other hand…” or “continuously…” to express a persistent change.

2. Structure

1. Verb (plain form) + 一方だ
   Used to indicate a state that is continually progressing, typically in a single direction.

2. Sentence A + 一方(で)、Sentence B
   Used to describe a contrast or coexistence between two situations.

3. Usage Explanation

• Indicating a Unidirectional Change or Trend:
  When used in the “Verb + 一方だ” structure, it emphasizes a situation that is continuing or intensifying, such as an increase or decrease.

• Expressing Contrast or Coexistence:
  When used in the “Sentence A + 一方で、Sentence B” structure, it emphasizes a contrast or coexistence of two situations, meaning “on one hand… on the other hand…”.

• English Translation:
  Can be translated as “on one hand…” “on the other hand…” or “continuously…”

4. Example Sentences

1. 環境問題は悪化する一方だ。
   Environmental issues are continually worsening.

2. 彼は勉強に集中する一方で、バイトもしている。
   On one hand, he’s focused on his studies; on the other, he’s working part-time.

3. 人口は増加する一方だ。
   The population is continuously increasing.

4. 都市は発展する一方で、自然が失われている。
   While cities develop, nature is being lost.

5. 経済は回復する一方、格差が広がっている。
   While the economy is recovering, the income gap is widening.

5. Key Points to Note

• For Unidirectional Change:
  The 「〜一方だ」structure is especially suited for describing irreversible changes, often with either positive or negative connotations.

• For Contrast and Parallel Structure:
  「〜一方で」is used to express contrast, with sentences in positive-negative or parallel relationships.

6. Similar Grammar

• 〜つつある: Used to describe a gradual process of change, often indicating a milder trend.
  • Example: 環境が改善されつつある。
    The environment is gradually improving.

7. Alternative Grammar

• 〜反面: Used to describe the opposite side of something.
  • Example: 彼は優しい反面、厳しい一面もある。
    He is gentle, but he also has a strict side.

8. Summary

「〜一方」is a versatile expression used to describe both unidirectional trends and the contrast or parallel features of two things. It is suitable for written and formal expression and is useful for explaining complex phenomena.