Femtogram
毫微微克(10的-15次方克)
🗣️ 情景例句
Where do you like to live, in the city or in the country?
你喜欢住在城市还是乡村？
I think so.
我想是这样。
Ken gave up smoking two years ago. He'd been smoking for thirty years.
两年前肯戒了烟，之前他抽了三十年烟。