Protoporphyrin
n. [化]原卟啉
🗣️ 情景例句
Sorry to be a pest.
不好意思打扰你。
I tried several times to call, but there is no answer.
我打了几次，但是没有人回答。
His cake is four times as big as mine.
他的蛋糕是我的四倍大。