Pentacarbonyl
五羰基
🗣️ 情景例句
I would like to send this by registered mail, please.
我想把这封信挂号寄出。
Reputation is often got without merit and lost without fault.
无功得名是常事，无过失名也是常事。
and is still non-existent in a number of 'civilized' nations.
今天，在许多文明国家里，义务教育迄今尚未实行。