TASK DEFINITION: Given a disfluent sentence, modify the sentence to it to its equivalent fluent form, preserving the meaning of the sentence.
PROBLEM: Wht do rock units what happens deeper in the earth I mean under what type of compression do they become thicker and shorten?

SOLUTION: Rock units become thicker and shorten when placed under this type of compression. 

PROBLEM: What region of the Rhine was changed by the Grand Canal d'Alsace no the Rhine Straightening program?

SOLUTION: What region of the Rhine was changed by the Rhine Straightening program?

PROBLEM: Who do public no preparatory schools in Scotland prepare to enter public schools?

SOLUTION:
Who do preparatory schools in Scotland prepare to enter public schools?