Quadrivalency
n. 四价
🗣️ 情景例句
Hi, Alexandra.
嗨， Alexandra。
Do you live across from the Public Hall?
你在大会堂对面居住吗？
It is all too easy to blame the railway authorities when something does go wrong.
因此，一旦铁路上真出了问题，人们便不加思索地责备铁路当局。