#1 - 5 Mistakes
There are are five things wrong with this sentence; only geniuses will be able to to spot all of the mitstakes
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1. The word "are" is repeated twice.
2. The word "to" is repeated twice.
3. The word mitstakes is misspelled. Its should be mistakes
4. The sentence is missing a punctuation mark and should end with a period/full stop not with semicolon.
5. Since there are only 4 mistakes, therefore, the statement of having five mistakes in the sentence is wrong which is the 5th mistake.
Or
Another theory is that the sentence should end with a period.