Xanthopterin
黄蝶呤, 2-氨基-4, 6-二羟基蝶呤
🗣️ 情景例句
Is smoking allowed on the train?
火车上允许吸烟吗？
Don't forget to accompany me.
不要忘记陪我。
The problem now facing humanity is: What is going to be done with all this knowledge?
用这些知识去做什么？