Explanation

  • Expresses doubt, uncertainty, or polite disagreement about a statement, proposal, or fact.
  • It questions the validity or wisdom of something without directly confronting or saying You're wrong.

Origin

  • Standard English construction expressing personal uncertainty (I'm not sure) regarding a specific topic (about that).

Alternatives

Slang/Informal:

  • Hmm, dunno 'bout that.
  • Is that right? (Can imply doubt)
  • Sounds kinda sus. (Suspicious)
  • I dunno... (Trailing off implies doubt)

Vulgar/Emphatic (Expressing strong doubt/disbelief):

  • I call bullshit on that.
  • That sounds like crap to me.
  • Are you fucking serious? I doubt that.

Milder/More Formal:

  • I would question that assumption.
  • I have reservations about that.
  • Further verification may be needed.
  • Permit me to express some skepticism.

Situational Appropriateness

  • Appropriate in most contexts, including professional and formal settings.
  • It's a polite and diplomatic way to express skepticism or potential disagreement without being confrontational.

Misunderstanding Warnings

  • Generally well-understood as expressing doubt or polite disagreement.
  • It's not a statement of ignorance (I don't know) but rather a questioning of the presented information or idea.

Examples

  • Person A: I think we should launch the product next week.
  • Person B: I'm not sure about that. The testing isn't complete yet.
  • He said the meeting is at 3. / I'm not sure about that, I thought it was at 4.
  • Is this the best route? / I'm not sure about that. Maybe we should check the GPS.

Dialogue

Manager: Let's assign the new project to Mark. He has the most experience.

Team Lead: I'm not sure about that. His current workload is already very high.

Manager: Good point. Who else could potentially lead it?

Social Media Examples

  • Comment on a news headline: I'm not sure about that source's credibility.
  • Forum Reply: (To a technical solution) -> I'm not sure about that method. It might cause conflicts.
  • Chat: Heard the party's cancelled. -> I'm not sure about that, I haven't heard anything.

Response Patterns

  • Oh? Why do you say that?
  • What makes you uncertain?
  • Okay, let's double-check.
  • Well, I think... (Reasserting the original point)

Common Follow-up Questions/Actions

After someone says I'm not sure about that:

  • They typically explain their reasons for doubt (...because I read somewhere else that...).
  • The conversation often turns to verifying the information or discussing the pros and cons of the proposal.

Conversation Starter

  • No. It's a response expressing doubt or uncertainty about something previously stated.

Intonation

  • Usually spoken with a thoughtful or hesitant tone.
  • Often has a slight pause after sure.
  • Intonation might fall slightly at the end, indicating reservation.

Generation Differences

  • Used by all generations.

Regional Variations

  • Universal in English-speaking regions.
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