Cephamycin
头霉素
🗣️ 情景例句
Yes, Mr. Tom. Let me check Miss Xu's schedule.
好，汤姆先生。让我查查徐小姐的日程表。
How long have you been studying English?
你学了多长时间的英语了？
It is only 380,000 kilometres away, and it has been visited by man already.
已经有人到过月球旅行了。