Sentence:  Who does not understand, as single parts of speech, all the common combinations which serve to connect and carry on construction, such as in-consequence-of, on-this-account, [...], and the like? Indeed, we are entitled to say of ordinary common-place speakers, that as they scarcely use <WSD>constructed language</WSD> except in forms already existing, so, with them, each thought finds an immediate sign in some familiar sentence; but then, be it observed, the parts which compose the sign have ceased to be separately significant: the sentences so used have been brought back to the condition of original or natural language, that of exclamations, — they have ceased to be logical, by having become purely rhetorical. 
Meaning of the word marked with <WSD> tags:  Any language used by people, as opposed to less civilized means of communication, such as the socialization between animals.