彼らが愛し合っているのを僕は知っている。

Sentence Analyzer

彼ら 愛し合っている 知っている

English Translation

I know they are in love with each other.

Furigana

(かれ)らが(あいあ)()っているのを(ぼく)()っている。

Romanji

Karera ga aishiatteiru no o boku wa shitteiru.

Words

彼ら (かれら)
they (usually male); them
()
indicates sentence subject (occasionally object); indicates possessive (esp. in literary expressions); but; however; still; and
愛し合う (あいしあう)
to love one another; to be affectionate towards each other; to have sex; to make love
()
indicates possessive; nominalizes verbs and adjectives; substitutes for "ga" in subordinate phrases; (at sentence-end, falling tone) indicates a confident conclusion; (at sentence-end) indicates emotional emphasis; (at sentence-end, rising tone) indicates question
()
indicates direct object of action; indicates subject of causative expression; indicates an area traversed; indicates time (period) over which action takes place; indicates point of departure or separation of action; indicates object of desire, like, hate, etc.
(ぼく)
I; me; you; manservant
()
topic marker particle; indicates contrast with another option (stated or unstated); adds emphasis
知る (しる)
to be aware of; to know; to be conscious of; to cognize; to cognise; to notice; to feel; to understand; to comprehend; to grasp; to remember; to be acquainted with (a procedure); to experience; to go through; to learn; to be acquainted with (a person); to get to know; to concern

Kanji

Readings: ヒ、 かれ、 かの、 か.の
Meanings: he, that, the
Readings: アイ、 いと.しい、 かな.しい、 め.でる、 お.しむ、 まな
Meanings: love, affection, favourite
Readings: ゴウ、 ガッ、 カッ、 あ.う、 -あ.う、 あ.い、 あい-、 -あ.い、 -あい、 あ.わす、 あ.わせる、 -あ.わせる
Meanings: fit, suit, join, 0.1
Readings: ボク、 しもべ
Meanings: me, I (male)
Readings: チ、 し.る、 し.らせる
Meanings: know, wisdom