Complexities
n. 复杂性(complexity的名词复数); 复杂的事物
🗣️ 情景例句
I'm really concerned about going away for the weekend, Ellen,
我这个周末出门实在放心不下， Ellen，
What are you writing?
你正在写什么？
Ethanol is more effective at a concentration of 50-70 percent;
乙醇的浓度为50％至70％时比较有效，