Don't Confuse 'Kariru' (to borrow) and 'Kasu' (to lend)! A Simple Rule to Remember
In English, "borrow" and "lend" are two different words. In Japanese, the same is true with 借りる (kariru) and 貸す (kasu). However, because they describe two sides of the same transaction, they are a very common point of confusion for learners. Mixing them up can completely reverse the meaning of your sentence!
But don't worry. There is a very simple trick to always get them right, and it all depends on the subject of the sentence—who is doing the action.
1. 借りる (Kariru): To Borrow (I am the borrower)
Use 借りる (kariru) when the subject of the sentence is the one receiving the item. The action is "borrowing from" someone. The key is that the subject (often "I" or "Watashi") is the borrower.
The sentence structure is: [Borrower] は [Lender] に/から [Item] を 借ります。
Example 1: Borrowing a book
私は山田さんに本を借りました。
(Watashi wa Yamada-san ni hon o karimashita.)
"I borrowed a book from Mr. Yamada."
Example 2: Can I borrow a pen?
すみません、ペンを借りてもいいですか？
(Sumimasen, pen o karite mo ii desu ka?)
"Excuse me, may I borrow a pen?" (Here, the implied subject "I" am the one borrowing).
2. 貸す (Kasu): To Lend (I am the lender)
Use 貸す (kasu) when the subject of the sentence is the one giving the item. The action is "lending to" someone. The key is that the subject (often "I" or "Watashi") is the lender.
The sentence structure is: [Lender] は [Borrower] に [Item] を 貸します。
Example 1: Lending a book
私は山田さんに本を貸しました。
(Watashi wa Yamada-san ni hon o kashimashita.)
"I lent a book to Mr. Yamada."
Example 2: Lending money
田中さんは鈴木さんにお金を貸しました。
(Tanaka-san wa Suzuki-san ni okane o kashimashita.)
"Mr. Tanaka lent money to Mr. Suzuki." (The subject, Tanaka-san, is the lender).
The Simple Rule: Focus on the Subject
To never get confused, just ask yourself: "Who is the subject of the sentence?"
- If the subject is the RECEIVER (borrower), use 借りる (kariru).
- If the subject is the GIVER (lender), use 貸す (kasu).
Look at the first two examples again. The only difference is the verb, but the meaning is completely opposite, all determined by who is doing the action.
私は山田さんに本を借りました。 (I borrowed from Yamada.)
私は山田さんに本を貸しました。 (I lent to Yamada.)
Conclusion
It's a simple switch, but it's a critical one. By always focusing on whether the subject of your sentence is the giver or the receiver, you can confidently choose the correct verb every time. Practice making a few sentences for each, and you'll never confuse kariru and kasu again!