If and Whether
If and Whether :
“If" is used frequently in casual speech and writing where some others would prefer “whether":
“I wonder if you would be willing to dress up as a giant turnip for the parade?" Revise to “I wonder whether. . . ." “If" can’t really be called an error, but when you are discussing two alternative possibilities, “whether" sounds more polished.
The two possibilities in this example are:
1) you would be willing
2) you wouldn’t.
In sentences using “whether" “or not" is often understood.)
Don’t substitute the very different word “whither," which means “where."
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