Many works have accordingly attempted to identify text units that are as parallel as possible from large corpora, and the task of measuring semantic textual similarity, which can find many uses, has received some attention lately (Agirre et al., 2012).
the main guidelines that they had to follow were that sure and possible paraphrases must be distinguished, smaller alignments were to be prefered but any-to-any alignments may be used, and sentences should be aligned as much as possible.