要补充说明以下情况才合理，即他们是最后一刻才获知这个问题。

It's only fair to add that they were not told about the problem until the last minute.

《牛津词典》

但他补充说，该领域的整体研究“仍处于起步阶段”，一个关键问题是，文学小说是否真的比其他小说更好。

But he added that the overall research in this area is "still in its infancy" and one key question is whether literary fiction really is better than other fiction.

youdao

有人担心人口的补充问题。

There is a concern about replenishment of the population.

《柯林斯英汉双解大词典》