between positive and negative polarity and discuss the importance of correctly analyzing the scope of the negation and the modality (e.g., whether the proposition is asserted to be real or not real).

A major annotation effort for temporal and event expressions is the TimeML specification language, which has been developed in the context of reasoning for question answering [@SauriVP06]. TimeML, which includes modality annotation on events, is the basis for creating the TimeBank and FactBank corpora [@Pustejovsky06; @Sauri09]. In FactBank, event mentions are marked with their degree of factuality.

Recent work incorporating modality annotation includes work on detecting certainty and uncertainty. Rubin  describes a scheme for five levels of certainty, referred to as Epistemic modality, in news texts. Annotators identify explicit certainty markers and also take into account Perspective, Focus, and Time. Focus separates certainty into facts and opinions, to include attitudes. In our scheme, focus would be covered by [*want*]{} and [*belief*]{} modality. Also, separating focus and uncertainty can allow the annotation of both on one trigger word. Prabhakaran et al. describe a scheme for automatic committed belief tagging. Committed belief indicates the writer believes the proposition. The authors use a previously annotated corpus of committed belief, non-committed belief, 