Hi, there will almost certainly be one or more of this question type on your test. In the past, there has been an average of slightly over 1.5 argument structures per exam, and it would be pretty irresponsible to simply not mention or teach a question type. That said, this is a pretty important skill. Being able to recognize the role played by a part of an argument is pretty integral to most LR questions (and to reading comp in general) so I would not completely deprioritize this section.