What's the difference between these sentences? (not less a than b, no less a than b)
"She is not less beautiful than her sister."
"She is no less beautiful than her sister."

Question

What's the difference between these sentences? (not less a than b, no less a than b)
"She is not less beautiful than her sister." 
"She is no less beautiful than her sister."

Answer

#1 would not be a natural comment to make, unless it were a contradiction

eg A: 'Mary is less beautiful than her sister'.
     B:  I disagree. She is NOT less beautiful than her sister'.

#2   is the correct form 'no less beautiful than', suggesting that the two sisters are equally beautiful.

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