Serosurvey
[医]血清学调查
🗣️ 情景例句
saying he was going to the railroad station
说他要去火车站
Politeness costs nothing and gains everything.
礼貌不费分文而可赢得一切。
After speaking for about half an hour he came to a sad part of the family history.
大约谈了半个小时之后，他谈到了家族史中的一件伤心事。