从第一只动物到其逐渐进化而成的后裔，如鸟、爬行动物和哺乳动物，都把抚养后代视为头等大事，它们为年轻的下一代殚心竭虑，关怀备至，操碎了心；

Those other first animals tended to their young, as do most of their descendants, such as birds, reptiles, and mammals, which still bring their young food and fight to protect them.

youdao

从第一只动物到其逐渐进化而成的后裔，如鸟、爬行动物和哺乳动物，都把抚养后代视为头等大事，它们为年轻的下一代殚心竭虑，关怀备至，操碎了心；

Those other first animals tended to their young, as do most of their descendants, such as birds, reptiles, and mammals, which still bring their young food and fight to protect them.

youdao