The most appropriate words that complete these sentences are doesn't, don't, and don't.
The sentence will need a negative word depending on whether this is coherent with a negative word.
For example "she is sad because she passed her exam" is not coherent because she would be sad only if she failed or didn't pass her exam.
Based on the above, the complete sentences would be:
Learn more about negative words in: https://brainly.com/question/17965175
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