这是因为在冬天的时候，人们更多的呆在室内，呼吸着同样的空气，互相传染细菌。

That is because, during the winter, people stay inside more and breathe the same air, sharing their germs.

youdao

这是因为在冬天的时候，人们更多的呆在室内，呼吸着同样的空气，互相传染细菌。

That is because, during the winter, people stay inside more and breathe the same air, sharing their germs.

youdao