English Language & Usage Stack Exchange is a question and answer site for linguists, etymologists, and serious English language enthusiasts. It's 100% free, no registration required.

Sign up
Here's how it works:
  1. Anybody can ask a question
  2. Anybody can answer
  3. The best answers are voted up and rise to the top

Possible Duplicate:
When are “if” and “whether” equivalent?

Which one is the correct meaning of "Let me know if the problem persists."? Or is it ambiguous?

  1. If the problem persists, let me know.

  2. Let me know whether the problem persists or not.

share|improve this question

marked as duplicate by FumbleFingers, jwpat7, aedia λ, Will Hunting, Mr. Shiny and New 安宇 Jan 10 '12 at 19:49

This question has been asked before and already has an answer. If those answers do not fully address your question, please ask a new question.

"Let me know if the problem persists" sounds to me like it means "if the problem persists, let me know". Option 2 sounds like you are putting words in the speaker's mouth. – Mr. Shiny and New 安宇 Jan 10 '12 at 19:50
@Mr.ShinyandNew安宇: Haha, good to know, thanks! :) – Mehrdad Jan 10 '12 at 19:54
up vote 5 down vote accepted


In informal writing, "if" and "whether" are used interchangeably.¹ This is not recommended because it creates ambiguity, but it is an unfortunate fact. Consequently, the statement can mean either:

Let me know whether the problem persists.


Let me know (only) if the problem persists.

share|improve this answer
@manishchristian Thank you for the edit. – MετάEd Apr 21 at 22:46

A logician might say that the person being addressed need say anything only if the problem did persist. In practice, the context will usually make it clear what is required.

share|improve this answer

Not the answer you're looking for? Browse other questions tagged or ask your own question.