**2.1 Participants**

The participants were 122 Japanese first-year students at a university in Japan. Fifty-nine students from three classes participated in this study in 2018, whereas

63 students from three classes participated in the study in 2019. All participants provided written informed consent before the study. All of them majored in law or political science and were enrolled in either regular English language classes or the intensive English language course, in both of which they were studying English as an EFL. The former class takes place twice and the latter four times per week. Generally speaking, students in the intensive English course tend to be more motivated to study English because they plan to study abroad. All of them had studied English for at least six years before entering the university.

Their English proficiency was intermediate, ranging from Level B1 to Level B2 according to the Common European Framework of Reference for Languages. They were taught how to write an essay and cite sources in the previous semester and had the experience of paragraph writing and essay writing. Thus, by the time of this essay assignment, the participants were supposed to understand the structure of the essay and paragraphs and citation rules. Some participants also wrote essays in other English classes; therefore, their writing expertise varied to some extent.
