Biolevel
生物水平面
🗣️ 情景例句
Thank you for calling us.
谢谢你打电话给我们。
I dropped the letter in the mailbox on the corner.
我把信放到角落上的邮箱里。
Well, I can't leave before nine. I have a lot of work to do.
嗯，我9：00以前离不开。我有很多作业要做。