Chalcomenite
蓝硒铜矿
🗣️ 情景例句
There's a time for everything.
事情要一件一件地做。
His courage is a lesson to us.
他很有勇气，是我们大家的榜样。
After lunch Aunt Huang came in and she looked worried.
午饭后黄阿姨来了，她面带愁容。