水は酸素と水素からできている。

water (esp. cool, fresh water, e.g. drinking water); fluid (esp. in an animal tissue); liquid; flood; floodwaters; water offered to wrestlers just prior to a bout; break granted to wrestlers engaged in a prolonged bout

topic marker particle; indicates contrast with another option (stated or unstated); adds emphasis

oxygen (O)

if; when; and; with; particle used for quoting (with speech, thoughts, etc.); quoting particle; promoted pawn; indicates question (sentence end)

hydrogen (H)

from (e.g. time, place, numerical quantity); since; from (originator); by; because; since; out of (constituent, part); through (e.g. window, vestibule); after; since

to be able (in a position) to do; to be up to the task; to be ready; to be completed; to be made; to be built; to be good at; to be permitted (to do); to become intimate; to take up (with somebody); to grow; to be raised; to become pregnant