用所给词的正确形式填空。

1. "Do you like noodles?" "No, I don’t like _____ at all."( they )

2. He often _____ letters to his mother. ( write )

3. Our _____ begin at 7:30 every morning. ( class )

4. We are twins. I have long hair, and she _____ long hair, too. ( have )

5. The _____ like milk and cakes. (baby)

实验动物按遗传学分类为（）

A、相同基因类型、不同基因类型、中间基因类型动物

B、近交系、封闭群、杂交群

C、同源突变系、同源导入系、分离近交系、重组近交系

D、遗传限定动物、免疫缺陷动物、转基因动物