A:② ③ ④ ⑤ ⑥表示鸡胚发育不同时期,它们是由①发育而来
B:胚胎发育过程中,最先出现血管,这有利于将营养物质运输给胚胎
C:胚胎发育过程中,因为其中营养被胚胎利用,卵黄和卵白越来越少
D:理论上讲,只要温度适宜,所有的鸡蛋都可以孵化出小鸡
Anna is a Chinese girl . She is ten . She is in London with her parents. She doesn't know much English. She can't speak English well. Sometimes her friends don't understand her .
It's Sunday morning .She is going to the zoo to see the panda . She is waiting at a bus stop .At the bus stop she asks a boy how to go to the zoo. But the boy can't understand her .Then she takes out a pen and some paper. She draw a panda on it and shows the picture to the boy .The boy smiles and then shows her the way to the zoo.
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