Mitchellite
镁铬铁矿
🗣️ 情景例句
What does John do?
John现在做什么事？
How many years have you been playing pingpong?
你打乒乓球多少年了？
He found it very difficult to get to sleep and he was rather angry with the man upstairs.
他觉得这样很难入睡， 他对楼上的人相当生气。