Impurity density
[电] 杂质密度
🧩 词语组成解析
🗣️ 情景例句
He had an emergency.
他有紧急事情。
You're dreaming!
别妄想！
It is eight o'clock.The children go to school by car every day, but today, they are going to school on foot.
现在是8点钟。孩子们每天都乘小汽车去上学，而今天，他们正步行上学。