In a functional grammar, the interpretation of language is understood as a system of meanings together with the forms that express those meanings (Halliday, 19942: xiii-xiv). In this sense we can state that is functional grammar is connected with semantics. We have chosen Systemic Functional Grammar as the linguistic framework because we are interested in studying how language is used in its context. Instead of having chosen independent examples coming from a computational corpus, we have decided to analyse some of the main processes of thematization (cleft sentence and reversed pseudo-cleft sentence) and postponement (existential sentence, pseudo-cleft sentence and extraposition) in English in the book Wouldn't Take Nothing for my Journey ...