[rossitter]

> "Please list the most important things that give meaning to your life"

The actual English-language version[0]:

> ...What about your life do you currently find meaningful, fulfilling or satisfying? What keeps you going and why?

So respondents in English were not prompted to list more than one item. What is not marked for plurality.

Unfortunately I've only been able to turn out the English-language prompts for this study.

As far as Korean goes, it might not require speakers to mark (certain) nouns for plurality, but there are of course common ways to do so when desired. There is a particle (들), and there are various modifiers that could be translated to e.g. some, several, many, a few, one or more... The difference is that if you use these modifiers, you don't (as in English et al.) have to make the noun "agree" in number. Roughly speaking, one or more thing would be fine.

[0]: https://www.pewresearch.org/global/2021/11/18/what-makes-lif... (under "How we did this")