彼は１日中大変忙しかった。

彼は１日中大変忙しかった。

He was very busy all day.

彼(かれ)は１日中(にちちゅう)大変(たいへん)忙(いそが)しかった。

Kare wa ichi nichichū taihen isogashikatta.

彼 (かれ)

he; him; his; boyfriend

は (は)

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

一 (いち)

one; best; first; foremost; beginning; start; bottom string (on a shamisen, etc.)

日中 (にっちゅう、ひなか)

daytime; during the day; Sino-Japanese

大変 (たいへん)

very; greatly; immense; enormous; great; serious; grave; dreadful; terrible; difficult; hard; major incident; disaster

忙しい (いそがしい、せわしい)

busy; hectic; occupied; engaged

Readings: ヒ、かれ、かの、か.の

Meanings: he, that, the

Readings: ニチ、ジツ、ひ、 -び、 -か

Meanings: day, sun, Japan, counter for days

Readings: チュウ、なか、うち、あた.る

Meanings: in, inside, middle, mean, center

Readings: ダイ、タイ、おお-、おお.きい、 -おお.いに

Meanings: large, big

Readings: ヘン、か.わる、か.わり、か.える

Meanings: unusual, change, strange

Readings: ボウ、モウ、いそが.しい、せわ.しい、おそ.れる、うれえるさま

Meanings: busy, occupied, restless