六年级英语首字母填空```急
A lot of people think that animals in the zoo are happy,but m_____of them are sad.Do you know why?Animals like tigers,lions,and bears usually live in f_____ or mountains.They run,jump,piay with their children and catch small animals f____ food.But now they have to stay in c____ or small rooms in the zoo.They do nothing but eat,walk and sleep every day.