Abstract：This paper analyses sentiment orientation of English sentences with modality. Sentences with modality are used widely in English, which comprise a significant proportion of typical reviews corpus. Due to the unique characteristics of modality, it is challenging for a general sentiment analysis system to handle these sentences. This paper identifies these sentences with the help of POS tagging and present a new modal feature that has been rarely discussed in previous studies. To further improve the accuracy, we develop a novel method which can effectively combine phrases sharing similar meanings of modality. The experimental results illustrate that the F-score of the proposed method increases by 4% and 7% than classic methods in the two-class and three-class sentiment orientation classifications, respectively.
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