There are a few things to consider with respect to writing an introduction for a discursive piece. They are as follows.
Before examining specific sections of a discursive response (such as the introduction in this case), it is important to adopt a logical structure/format that begins with the introduction. Here, you may wish to consider the fact that the introduction of a discursive piece differs from those of other essays in the sense that there is no need to include a formal thesis statement. Instead, introducing your topic can be done through the use of anecdotes or by asking questions. This will in turn assist you in gaining the reader's attention and subsequently introduce them to your topic. Whether you may wish to do so in an implicit or explicit manner is subject to your own consideration.
Based on the above, effective ways to start discursive responses include:
- Highlighting an example - Particular examples can enable readers to develop an understanding of the subject of your discursive piece, as well as an awareness of their own opinion in that regard.
- Asking a question - Questions are beneficial given that they encourage readers to reflect upon their own knowledge of the topic of your discursive response.
- Using an anecdote - Personal experience (whether real or hypothetical) can develop a particular rapport with a reader because it allows them to perceive the manner in which another person engages with a specific topic/idea.
I hope this helps!