Ectomesoderm
外中胚层
🗣️ 情景例句
Spring has sprung and all the flowers are blooming.
春天来了。花儿都开了。
Why are you so mean? I've never done anything to you.
凶什么凶？ 我又没得罪你。
Did you buy one, sir?
你买了票吗，先生？