Given a disfluent sentence, modify the sentence to it to its equivalent fluent form, preserving the meaning of the sentence.

Q: What keeps the sensitivity of hormones at the same level, oh I mean the immune system?

A: What keeps the sensitivity of the immune system at the same levels? 
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Q: What do petrologists no what do unstable isotope studies indicate?

A: What do unstable isotope studies indicate?
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Q: What event was won by Yale in 1920 or rather what stadium was built in 1920?

A:
What stadium was built in 1920?
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