Comparison of「〜ながら」 and「〜たり〜たり」

Both 「〜ながら」 and 「〜たり〜たり」 are used to describe multiple actions happening either simultaneously or alternately, but they differ in usage and meaning. Below is a detailed comparison.

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1. The Usage of「〜ながら」

「〜ながら」 is mainly used to indicate two actions happening at the same time, similar to “while doing…” in English.

Grammar Structure

Verb stem (remove ます from the ます-form) + ながら

Usage

1. Indicates two simultaneous actions (with a clear primary action)

   • Example: 「音楽を聞きながら、勉強する。」

     • (Study while listening to music.)
     • Here, 「音楽を聞く」(listening to music) is the secondary action, while 「勉強する」(studying) is the primary action.

2. The subject must be the same for both actions

   • Example: 「彼は笑いながら話す。」

     • (He talks while laughing.)

   • The subject of both 「笑う」 (laugh) and 「話す」 (talk) is 「彼」(he).

3. Can be used for internal thoughts or contradictions

   • Example: 「悪いと知りながら、彼は嘘をついた。」

     • (Even though he knew it was wrong, he lied.)

   • Expresses the nuance of “despite knowing something, still doing it.”

Cannot be used when the subjects are different

Incorrect example:
❌「私は歩きながら、彼は歌った。」

• The two actions must have the same subject, so 「ながら」 cannot be used here.

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2. The Usage of「〜たり〜たり」

「〜たり〜たり」 is used to list multiple alternating actions, similar to “sometimes doing A, sometimes doing B” in English.

Grammar Structure

Verb (past tense) + り + Verb (past tense) + りする

Usage

1. Indicates multiple actions happening alternately

   • Example: 「休みの日は、テレビを見たり、本を読んだりする。」

     • (On my day off, I sometimes watch TV, and sometimes read books.)

   • This emphasizes alternating actions, rather than simultaneous actions.

2. Used to list multiple activities

   • Example: 「旅行では、海で泳いだり、山に登ったりしました。」

     • (During the trip, I swam in the sea and climbed mountains.)

   • Implies that there may be other activities as well, not just the ones listed.

3. The subjects can be different

   • Example: 「私は歌ったり、彼は踊ったりした。」

     • (I sometimes sang, and he sometimes danced.)

   • Unlike 「ながら」, 「たり〜たり」 can be used with different subjects.

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3. Comparison of「〜ながら」 and「〜たり〜たり」

Aspect	〜ながら	〜たり〜たり
Meaning	Simultaneous actions	Alternating actions
English equivalent	“While doing…”	“Sometimes doing A, sometimes doing B”
Subject requirement	Must be the same	Can be different
Number of actions	Usually two	Can list multiple
Example	音楽を聞きながら、勉強する。 (Study while listening to music.)	休みの日は映画を見たり、本を読んだりする。 (On my day off, I sometimes watch movies and sometimes read books.)

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4. When Can They Not Be Interchanged?

❌「〜たり〜たり」 Cannot Replace「〜ながら」

• Example: 「彼は笑いながら話す。」（✔️）
• Incorrect: 「彼は笑ったり話したりする。」（❌）

  • This sentence means “he sometimes laughs and sometimes talks,” which is not the intended meaning.

❌「〜ながら」 Cannot Replace「〜たり〜たり」

• Example: 「私は泳いだり、走ったりした。」（✔️）
• Incorrect: 「私は泳ぎながら走った。」（❌）

  • Since swimming and running cannot happen at the same time, 「ながら」 is incorrect.

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5. Summary

• 「〜ながら」 → Used when two actions happen at the same time (same subject required).
• 「〜たり〜たり」 → Used when multiple actions happen alternately (different subjects allowed).

If you want to say “Listening to music while studying“, use 「ながら」.
If you want to say “On my day off, I sometimes watch TV and sometimes read“, use 「たり〜たり」.