身体 (shēn tǐ) means body or health. 身 refers to the body or self and 体 means body or substance. In context, 身体 can mean the physical body (身体检查, physical examination) or health as a state (身体好, good health; 身体不舒服, not feeling well). The common expression 身体是革命的本钱 (health is the capital for revolution) is a Mao-era saying still used to emphasise the importance of health. Asking 身体怎么样? is a caring way to enquire about someone's wellbeing.