According to the register of English language, collocations fall under three categories: formal, informal and neutral, as following: 1. Formal collocations are found in official or academic writing and in official legal speech, for example: submit assignments, request an extension, consulting a tutor, subject to police investigation, etc.; 2. Informal collocations are used in conversations, personal letters and emails and sometimes in journalism, for example: to dig out info about, totally awesome, to not have a clue/ the foggiest idea, to grab a snack, etc.; 3. Neutral collocations are found in journalistic texts, for example: investigating/ looking into, to probe, hand in assignments, ask for an extension, have a word with, etc.