The correct expression below is:

老鼠追在大象 lǎo shǔ zhuī zài dà xiàng.
小猫追老鼠在 xiǎo māo zhuī lǎo shǔ zài.
小狗在追小猫 xiǎo gǒu zài zhuī xiǎo māo.
在老虎追小狗 zài lǎo hǔ zhuī xiǎo gǒu.