胚胎发育
参考答案：
是指从单细胞的合子卵裂开始至发育成为内外器官俱全的胚胎个过程。
句型转换。
1. He studies at No.1 Middle School. (改为否定句)
He _________ _________ at No.1 Middle School.
2. He plays basketball very well. (改为同义句)
He is _________ _________ playing basketball.
3. My brother walks to the school every day.(改为同义句)
My brother goes to school __________ _________ every day.
4. She never goes roller skating. (对划线部分提问)
__________ _________ does she go roller skating?
5.There is some bread on the table.(改为一般疑问句)
_________ there _________ bread on the table?
梁桥实际最大剪应力截面应设置在支座上。( )
