彼らは泳がなかった、なぜなら寒かったからである。
Sentence Analyzer
English Translation
They didn't swim because it was cold.
Furigana
Romanji
Karera wa oyoganakatta, naze nara samukatta kara de aru.
Words
彼ら
(かれら)
they (usually male); them
は
(は)
topic marker particle; indicates contrast with another option (stated or unstated); adds emphasis
泳ぐ
(およぐ)
to swim
何故
(なぜ、なにゆえ)
why; how
だ
(だ)
be; is; indicates past or completed action; indicates light imperative
寒い
(さむい、さぶい)
cold (e.g. weather); uninteresting (esp. joke); lame; dull; weak; corny
から
(から)
from (e.g. time, place, numerical quantity); since; from (originator); by; because; since; out of (constituent, part); through (e.g. window, vestibule); after; since
或
(ある)
a certain ...; some ...