zǎo / qī / yǔ / zhòu / zhōng / zhǔ / yào / cún / zài / de / shì / qīng / hé / hài / děng / qīng / yuán / sù

早期宇宙中，主要存在的是氢和氦等轻元素。

In the early universe, the main elements present were light elements such as hydrogen and helium.