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

Ex Input:
What do petrologists no what do unstable isotope studies indicate?

Ex Output:
What do unstable isotope studies indicate?


Ex Input:
What can an old, ill man do or rather not do?

Ex Output:
What can and old, ill man not do?


Ex Input:
When did Great Khan leave oh when did Mongke Khan kill him?

Ex Output:

 When did Mongke Khan kill Great Khan?