Теория:
To speak about vitamins, you need the appropriate vocabulary. Part 1

balance – баланс
behaviour – поведение
combination – сочетание
component – компонент
contain – содержать
daily – ежедневный
diet – диета
dietary – диетический
eyesight – зрение
fuel – топливо
function – функция, функционировать
growth – рост
leafy vegetables – листовые овощи
liquid – жидкость
Examples:
What vitamins are good for the eyesight?
We often eat leafy vegetables for supper.
Источники:
https://www.babycenter.com/0_the-lowdown-on-childrens-vitamins_64355.bc