The aim of the study described in this paper is to verify whether the structure of a modal predicate influences the type of modality expressed by the English modal verb should. The study uses language samples excerpted from The Corpus of Contemporary American English. It has adopted the model of the semantic field of modal expressions proposed by Angelika Kratzer. Additionally, this framework has been used to determine types of modality in this study. The analysis focuses on the interaction within the semantic field of the modal should with various forms of the main verb within the modal predicate structure.