ペンが必要なら貸してあげよう。

ぺんが必要なら貸してあげよう。

If you need a pen, I'll lend you one.

ペンが必要(ひつよう)なら貸(か)してあげよう。

Pen ga hitsuyō nara kashiteageyou.

ペン (ペン)

pen

が (が)

indicates sentence subject (occasionally object); indicates possessive (esp. in literary expressions); but; however; still; and

必要 (ひつよう)

necessary; needed; essential; indispensable; necessity; need; requirement

だ (だ)

be; is; indicates past or completed action; indicates light imperative

貸す (かす)

to lend; to loan; to rent out; to hire out

Readings: ヒツ、かなら.ず

Meanings: invariably, certain, inevitable

Readings: ヨウ、い.る、かなめ

Meanings: need, main point, essence, pivot, key to

Readings: タイ、か.す、か.し-、かし-

Meaning: lend