Talking about body and feeling
Russian uses some signature constructions for the body that don't translate word-for-word. The dative pops up again — when something hurts, the person who feels the pain takes the dative.
'Something hurts me' — у меня болит
Literally: 'at-me [it] hurts'. The body part is the GRAMMATICAL subject (in nominative); the person who feels it is in у + genitive. - У меня болит голова. = My head hurts (lit. 'at-me hurts head'). - У него болит зуб. = His tooth hurts. - У Анны болят ноги. = Anna's legs hurt. (plural body part → plural verb болят.)
Body parts vocabulary (singular and plural)
Many body parts come in pairs and use the plural form naturally: - Голова (head), голос (voice). - Глаз / глаза (eye / eyes). - Рука / руки (arm-hand / arms-hands). - Нога / ноги (leg-foot / legs). - Зуб / зубы (tooth / teeth). - Ухо / уши (ear / ears — irregular plural).
Feeling: чувствовать себя
Чувствовать себя = to feel (oneself). The person is in nominative, and an adverb (or adjective in instrumental) describes how: - Я чувствую себя хорошо. = I feel good. - Анна чувствует себя плохо. = Anna feels bad. - Как ты себя чувствуешь? = How are you feeling?
'Sick' constructions
Болеть has two meanings: - Что-то болит у меня (3rd person) = something hurts (the body-part construction above). - Я болею = I am sick (with an illness). For a specific illness use the instrumental: Я болею гриппом. = I have the flu (lit. 'I am-sick with-flu').
