コロンブスは地球は丸いと主張した。

コロンブスは地球は丸いと主張した。

Columbus argued that the earth was round.

コロンブスは地球(ちきゅう)は丸(まる)いと主張(しゅちょう)した。

Koronbusu wa chikyū wa marui to shuchōshita.

は (は)

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

地球 (ちきゅう)

the earth; the globe

丸い (まるい、まろい)

round; circular; spherical; harmonious; calm

と (と)

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

主張 (しゅちょう)

claim; request; insistence; assertion; advocacy; emphasis; contention; opinion; tenet

Readings: チ、ジ

Meanings: ground, earth

Readings: キュウ、たま

Meanings: ball, sphere

Readings: ガン、まる、まる.める、まる.い

Meanings: round, full (month), perfection, -ship, pills, make round, roll up, curl up, seduce, explain away

Readings: シュ、ス、シュウ、ぬし、おも、あるじ

Meanings: lord, chief, master, main thing, principal

Readings: チョウ、は.る、 -は.り、 -ば.り

Meanings: lengthen, counter for bows & stringed instruments, stretch, spread, put up (tent)