アプリで漢字を練習します。
I practise kanji with an app.
アプリ is the means.
Use で to name a method or tool as well as the place where an action happens. Ask どうやって when you specifically want to know the method.
『アプリで勉強します』は方法、『図書館で勉強します』は場所を伝えます。

Put a tool or method before で: アプリで、ネットで、本で. Keep the verb to show what the person does with it.
『アプリで練習します』では、アプリを使うことを伝えます。
A place followed by で can tell where an action takes place: 図書館で読みます. The same particle has a different role.
『図書館で読みます』では、読む場所を伝えます。
Use どうやって勉強しますか to ask how someone studies. A question with どこで often asks about a place, though the answer can sometimes mention a method.
方法をはっきり聞きたいときは、『どうやって』を使います。
Do not translate every で as by or at. Identify the noun and the action. This lesson covers method and action location, not every use of で.
『電話で話します』と『家で話します』では、電話と家の役割が違います。
These scenes and exercises are fictional examples written for this lesson.
アプリで漢字を練習します。
I practise kanji with an app.
アプリ is the means.
図書館で漢字を練習します。
I practise kanji at the library.
図書館 is the location.
どうやって日本語を勉強しますか。
How do you study Japanese?
Ask about a method.
友達と電話で話します。
I talk with a friend on the phone.
電話 is the means; 友達 is the person.
Say your answer before opening the explanation.
Q1. Choose a method: アプリで / 図書館で。
アプリで。
An app is a tool; a library is a place.
Q2. Ask specifically how someone studies Japanese.
どうやって日本語を勉強しますか。
どうやって asks about the method.
Q3. In 家で本を読みます, does 家で name a place or a tool?
場所です。
家 is a place.
Q4. Say that you practise with a book.
本で練習します。
Put the means before で.
| Japanese | English |
|---|---|
| 手段 | means; method |
| 場所 | place |
| 図書館 | library |
| 電話 | telephone |
| 練習します | practise |
どうやって練習しますか。
How do you practise?
Grammar reference: The Japan Foundation, Irodori: Japanese for Life in Japan, Elementary 1. Explanations are concise original summaries; practice examples are original.