If I were you, I ________ that laptop. It’s much too expensive.
In the first blank, we can either use " would buy" or "wouldn't buy" as the second statement has negative charge we will use " wouldn't buy".
If I were you, I wouldn't buy that laptop. It’s much too expensive .
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"Won't" is the short form of "will not". 'Wouldn't" is the short form of "would not" and would is the past form of will. Won't and wouldn't are very common and informal in use, whereas will not and would not are usually formal
If I were you, I wouldn't buy that laptop. It’s much too expensive