What is the reason why rabbits tremble?

Ambient temperature, when the weather is hot, rabbits have a lot of hair, so they can't sweat and get rid of the shivering caused by heat. If the temperature is too low, rabbits will tremble and even catch a cold. Afraid, rabbits are timid, and they may tremble with fear when they see strange things; The environment is noisy, and the rabbit's hearing is very keen. Too noisy environment will also make it tremble.