What are the names of a male and a female pair of pets?

As follows:

1. Lala, Sarah, PayPal, Dolphin.

2. Doudou, Zhuli, Nana, Susu.

3. A Bao, Xiong Xiong, Nao Nao, Jiao Jiao.

4. Big money, Harry, Dangdang, Diandian.

5. Maomao, Huniu, Smelly, Silk Road.

6. Dalai, Xindi, Beier, Xiaoxue.

7. Benben, Kaidi, Preserved Egg, Ruoruo.

8. Doudou, Buck, Huahua, and Qiqi.