非常嚴重。美國每年有N萬人會死於肺炎，高齡者居多。

來源: 大江川於 2015-07-10 17:07:47 [博客] [舊帖] [給我悄悄話] 本文已被閱讀：次

WENXUECITY.COM does not represent or guarantee the truthfulness, accuracy, or reliability of any of communications posted by other users.