Pentafluorination
五氟化反应
🗣️ 情景例句
to serve the senior citizens
为Riverdale的老年人
There isn't much room for doubt in this matter.
关于这件事，不大有质疑余地。
In 1898 a law was passed which meant that all people above a certain age were paid a weekly old-age pension.
1898年通过了一项法令，规定一定年龄以上的人全都可以按周领取"老年养老金。