てしまう / ちゃう means finish completely; do accidentally. It is a JLPT N4 Japanese grammar pattern used to express this idea in natural Japanese.
This English meaning is written independently from the source list so it answers the learner question directly: what does てしまう / ちゃう mean and when should you use it?
What does てしまう / ちゃう mean?
Use てしまう / ちゃう when you want to express finish completely; do accidentally in a Japanese sentence.
Natural translations include:
- finish completely; do accidentally
- finish completely
- do accidentally
How to form てしまう / ちゃう
Verb て-form + しまう / ちゃう
Examples of the pattern:
- Verb て-form + しまう / ちゃう
- てしまう / ちゃう
- related form: てしまう
When is てしまう / ちゃう used?
Use てしまう / ちゃう in situations like:
- reading or writing JLPT N4-level sentences
- making a sentence more precise than a basic N5 pattern
- recognizing natural grammar in conversation or short passages
Tone and register:
- usually neutral unless the pattern itself is casual, humble, honorific, or written
- common in JLPT N4 grammar study and everyday examples
てしまう / ちゃう example sentences
- 宿題を全部やってしまいました。 — I finished all of my homework.
- 財布を忘れてしまいました。 — I accidentally forgot my wallet.
- ケーキを全部食べちゃった。 — I ate the whole cake.
- 大切なメールを消してしまいました。 — I accidentally deleted an important email.
- この本を一日で読んでしまいました。 — I finished reading this book in one day.
Nuance of てしまう / ちゃう
The key nuance is finish completely; do accidentally in context, not a word-for-word English replacement.
This matters because てしまう / ちゃう often changes the relationship between actions, people, time, or evidence in the sentence. Read the whole sentence before choosing the English translation.
てしまう / ちゃう vs てしまう
Both patterns can appear in related sentences, but they do different jobs.
てしまう / ちゃう:
- is the target JLPT N4 pattern in this lesson
- focuses on finish completely; do accidentally
てしまう:
- is useful for comparison because learners often confuse nearby forms
- may change the tone, evidence, direction, or relationship in the sentence
Quick contrast examples:
- Target pattern: 宿題を全部やってしまいました。 — I finished all of my homework.
- Related pattern with てしまう: compare what changes in evidence, timing, direction, or politeness.
Common mistakes with てしまう / ちゃう
Watch out for these mistakes:
- Copying a dictionary gloss without checking the sentence context
- Using the wrong verb, adjective, or noun form
- Confusing てしまう / ちゃう with てしまう because the English can sound similar
Is てしまう / ちゃう on the JLPT?
Yes. てしまう / ちゃう is connected to JLPT N4 grammar in this blog.
That means learners should be able to:
- recognize it in reading
- understand its nuance in context
- use it in simple original sentences
Practice questions for てしまう / ちゃう
Try making your own sentences with these prompts:
- Write one short sentence using the basic structure.
- Replace the subject, time, or object and keep the same grammar point.
- Compare your sentence with the related pattern above.
Learn てしまう / ちゃう with Kanjiru
If you want to review てしまう / ちゃう together with kanji, vocabulary, and other JLPT N4 patterns, Kanjiru helps you practice Japanese in short, focused sessions.
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