Ectomesoderm
外中胚层
🗣️ 情景例句
Rome wasn't built in a day.
冰冻三尺，非一日之寒。
What do you like to do in your spare time?
空闲时你喜欢干什么？
sank with all flags flying----in the harbour of the birth.
带着全身飘扬的彩旗，沉没在了它诞生的港口。