几乎所有患者都是六岁以下的儿童，其中大多数都不到两岁。

Nearly all of the cases have been among children younger than six, with most under two.

youdao

几乎所有患者都是六岁以下的儿童，其中大多数都不到两岁。

Nearly all of the cases have been among children younger than six, with most under two.

youdao