Ectomesoderm
外中胚层
🗣️ 情景例句
Hello, Miss Huang. How are you?
喂，黄小姐，你好吗？
The tour will take about an hour and a half. We ought to be back here by 3:00.
参观大概要一个半小时，3点钟以前回到这里。
Look at the snow! It's thick, isn't it?
瞧这雪！雪很厚，是吧？