30. The system of claim 21 , wherein the comparing comprises selecting a sequence of corresponding text fragments for the input text.
30. The system of claim 21 , wherein the comparing comprises selecting a sequence of corresponding text fragments for the input text. 34. The system of claim 30 , wherein the comparing further comprises: inputting the input text to a statistical model to divide the input text into a sequence of input text fragments; and selecting the sequence of corresponding text fragments from one or more candidate sequences matching the sequence of input text fragments.