Sentence:  Palmer (1986:26–28) suggested that all languages have a clear way of indicating that the speaker is making a statement which (s)he believes to be true. Such statements are usually expressed by the <WSD>declarative</WSD> grammatical structure and the respective mood is called either "<WSD>declarative</WSD>" or "indicative"... 
Meaning of the word marked with <WSD> tags:  Expressing truth.