Practice 2　　On some occasions it is important to adhere to the conventions that characterize serious public discourse and to avoid expressions that we might use in more casual situations. Among the features of formal English are the careful explanation of background information, complexity in sentence structure, explicit transitions between thoughts, and the use of certain words that are reserved chiefly for creating a formal tone. Situations that normally require formal usage would include an article discussing a serious matter submitted to a respected journal, an official report by a group of researchers to a government body, a talk presented to a professional organization, and a letter of job application.