What's The Difference? 貸す (kasu) Vs. 借りる (kariru) – A Simple Guide To "Lend" And "Borrow" – JPLT Online Japanese Language Training School

(Joy lending a pen [Kasu] vs. Joy borrowing a pen [Kariru])

“Please borrow me a pen.” (Mistake!)
“Please lend me a pen.” (Correct!)
In Japanese, 貸す (Kasu) is to lend, and 借りる (Kariru) is to borrow. Mixing these up is a very common mistake. Let’s learn the easy way to remember with Joy and Ken!

🗣 Conversation Scene

Joy forgot her umbrella. It is raining.

Joy

あ、雨（あめ）ですね。傘（かさ）がありません。
ケンさん、貸（か）してください！
(Ah, it’s raining. I don’t have an umbrella. Ken, please “lend” me one!)

Ken

いいですよ。どうぞ。
いつでも借（か）りてくださいね。
(Sure. Here you go. Please “borrow” it anytime.)

💡 Explanation

Check the direction of the item!

Point 1: Kasu (貸す) = Lend (Give)

The item moves AWAY from the subject. You give it to someone temporarily.

🔑 Easy Mnemonic:
KaSU = SUpply (or Send)

（私が）ペンを貸す。
(I lend a pen.)
お金（かね）を貸してください。
(Please lend me money. [You do the action])

Point 2: Kariru (借りる) = Borrow (Get)

The item comes TOWARDS the subject. You receive it from someone temporarily.

🔑 Easy Mnemonic:
KaRIru = REceive

（私が）本（ほん）を借りる。
(I borrow a book.)
トイレを借りてもいいですか？
(May I borrow/use the toilet? [Can I do the action?])

📊 Comparison Table

Word	Meaning	Direction	Particle
貸す (Kasu)	Lend	Out (Give) ➔	[Someone] に貸す
借りる (Kariru)	Borrow	In (Get) ⬅️	[Someone] に/から借りる

🚧 Joy’s Mistake

(Requesting a pen from Ken)

❌ Wrong: ペンを 借（か）りて ください！
(Translation: “Please borrow a pen [from someone else]!” Ken will be confused. “Why do I have to borrow a pen? I have one!”)

✅ Right: ペンを 貸（か）して ください！
(Translation: “Please lend [me] a pen.” This asks Ken to give the pen to Joy.)