Opv
[医][=oral polio vaccine]口服脊髓灰质炎疫苗
🗣️ 情景例句
I'm really sorry to hear about that.
听到这个消息真让我感到难过。
Empty wagons rattle loudest.
空车响声大。
giant hovercraft liners could span the Atlantic;
大型的气垫班轮或许能跨越大西洋。