Hi. I'd like to know how you use this phrase. To introduce some amazing or unbelievable topic? Thank you.
Hello, Guest,
Shouldn't it be "you can't make up this stuff"?
This phrase is normally used to describe something that we know to be true, but is amazing or unusual. You would usually find it hard to believe, but you have evidence of it being factual or true. The second part is important. You would not normally use this phrase with things that you don't know or believe to be true.
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 pieanne's reply was promoted to an answer.
Hi pieanne.

"Make up" is a phrasal verb, but it can be split up in a sentence as the original poster has done.

"You can't make this stuff up" and "You can't make up this stuff" both make sense, but I would personally tend towards the first, especially in spoken English.
OK, B smith, Thank you! Emotion: smile
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