18. A computer-readable storage medium containing instructions for classifying sentences, by a method comprising: providing a sentence classifier to classify sentences based on feature representations of the sentences and classifications of the sentences, the classifier being trained using training data; receiving a sentence; generating a feature representation of the sentence; and applying the provided sentence classifier to the generated feature representation of the sentence to classify the sentence wherein the feature representations include a pattern feature and wherein the pattern feature is based on support of a generalized sentence of a sentence to be a generalized sentence pattern of sentences within training data.
21. The computer-readable storage medium of claim 18 wherein support is defined as: 
 sup( p )=|{ s|s∈S p ⊂ s}| where sup(p) represents the support of generalized sentence p to be a generalized sentence pattern, s is a generalized sentence in the set of sentences S, |X| represents the number of elements in a set X, and p ⊂ s indicates whether the generalized sentence s contains the generalized sentence p.