…
Questions & Answers about kore ha hon desu.
What does これ mean and what kind of word is it?
これ is a demonstrative pronoun meaning this (thing)—it stands in for a noun that is close to the speaker. In English we might say “this” on its own, but in Japanese これ replaces the noun entirely rather than modifying it.
Why is は used after これ, and what does it indicate?
は is the topic-marker particle. It tells us that これ (“this”) is what we’ll be talking about. A rough breakdown:
- これ (this) → topic of the sentence
- は marks “this” as the topic
By marking “this” as the topic, the rest of the sentence comments on or describes it.
Why isn’t there a particle after 本? Shouldn’t every noun have a particle?
In a copular sentence of the form A は B です, B is simply the predicate noun (the complement of the copula) and doesn’t need an extra particle. Here’s the structure:
- Topic: これ は
- Predicate noun: 本
- Copula: です
Since 本 is directly linked to です, no additional particle is required.
What is です, and why do we use it here?
です is the polite copula, equivalent to the English verb “to be” in its polite form. In これ は 本 です (“This is a book”), です:
- Links the topic to its description (“is”)
- Adds a polite tone (appropriate in most everyday situations)
Why can’t we use が instead of は in this sentence?
が marks the grammatical subject or the focus of new information, while は marks the topic (the thing you’re talking about). If you say これ が 本 です, it sounds like you’re emphasizing “this” as the one-and-only thing that is a book (e.g. answering “Which one is the book?”). By using は, you’re simply stating “As for this, it is a book,” which is the standard way to define or identify something.
Can I drop です and still be correct?
In casual speech you can replace です with the plain copula だ, or even omit it in very informal contexts. For example:
- Casual: これは本だ。
- Very informal (e.g. notes, slang): これ、本だ。
However, in formal or polite situations you should keep です.
What’s the difference between これ and この?
- これ is a demonstrative pronoun: it stands alone and means “this (thing).”
- この is a demonstrative adjective (a prefix) that must modify a noun: it means “this [noun].”
• この本 = “this book” (you need 本 after この)
• これ = “this one/book” (no noun follows)
How do I make the sentence negative?
You can negate the copula. In polite speech:
- これは本ではありません。 (very polite)
Or in more conversational style: - これは本じゃないです。
- これは本じゃない。 (plain/casual)
More from this lesson
AI Language TutorTry it ↗
“How do verb conjugations work in Japanese?”
Japanese verbs conjugate based on tense, politeness, and mood. For example, the polite present form adds ‑ます to the verb stem, while the past tense uses ‑ました. Unlike English, Japanese verbs don't change based on the subject — the same form works for "I", "you", and "they".
Sign up free — start using our AI language tutor
Start learning JapaneseMaster Japanese — from kore ha hon desu to fluency
All course content and exercises are completely free — no paywalls, no trial periods.
- ✓ Infinitely deep — unlimited vocabulary and grammar
- ✓ Fast-paced — build complex sentences from the start
- ✓ Unforgettable — efficient spaced repetition system
- ✓ AI tutor to answer your grammar questions