Ccsf
[醫][=cerebrospinal fluid(drug)concentration]腦脊液（藥物）濃度
??? 情景例句
Who's the patient?
病人是誰？
What happened to you memory?
你的記性是怎么搞的？
It's about a time when there were black slaves in North America. It's about their fight for freedom.
（它）講的是有一段時期，北美洲存在黑奴。影片講述他們為自由而斗爭的情況。