English learners may improve their writing skills in the language if they focus on making good arguments rather than mastering complex grammar and vocabulary, according to new Japanese research.

The study — the first of its kind — by Kobe University linguistics professor Sachiko Yasuda was published on Thursday in the journal Assessing Writing.

In 2023, Yasuda conducted an experiment in which she had 102 students at a public secondary school in Japan write an argumentative essay on an assigned topic in English. She then let two writing experts — who did not know the purpose of the experiment — grade their essays.