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Breakdown of simekiri wo mamoruno ha touzen da to omou.
はha
topic particle
をwo
direct object particle
〜の〜no
verb nominalizer
とto
quotative particle
思うomou
to think
だda
to be
締め切りsimekiri
deadline
守るmamoru
to meet (a deadline)
当然touzen
natural
Questions & Answers about simekiri wo mamoruno ha touzen da to omou.
What does the particle を do in 締め切りを守る?
を marks the direct object of a transitive verb. Here, 締め切り (deadline/closing date) is what is being “kept/observed,” and 守る is the action applied to it. So 締め切りを守る = “to meet/observe the deadline.”
Why is の used after 守る? Could I use こと instead?
の nominalizes the verb phrase, turning “to keep the deadline” into a noun-like chunk so it can be the topic: 守るのは = “as for keeping (it) …”. こと can replace の here with little change in meaning:
- 締め切りを守るのは当然だ
- 締め切りを守ることは当然だ Nuance: の is a bit more colloquial/immediate; こと sounds slightly more formal/abstract. Both are fine.
Why is は after 守るの instead of after 締め切り?
With 締め切りを守るのは, the topic is the action “keeping deadlines,” not “deadlines” themselves. If you instead want to topicalize “deadlines,” you can say:
- 締め切りは守るのが当然だ = “As for deadlines, keeping them is natural.” This shifts the focus from the act to the thing.
Can I use が instead of は (i.e., 締め切りを守るのが当然だ)? What’s the difference?
Yes. Rough nuance:
- 〜のは当然だ: topicalizing; presumes shared context and presents a general stance. Often sounds a bit more opinionated/contrastive.
- 〜のが当然だ: neutral subject marking; states the fact “the act of doing X is natural.” Both are acceptable; choose based on whether you want to set “doing X” up as the topic or simply identify it as the subject.
What exactly does と思う mean here, and what is と doing?
と思う means “I think (that) …”. と is the quoting particle; it marks the preceding clause as the content of your thought. So 当然だ is being quoted in your mind: “(I) think ‘it’s natural’.” The quoted clause must come right before と思う; you can’t move と elsewhere.
Why is there a だ before と思う? Can I drop it?
当然 is a na-adjective, so when it functions as a predicate before と思う, it needs だ: 当然だと思う. In careful speech and writing, keep the だ. In casual conversation some speakers omit it (e.g., 当然と思う), but many consider that sloppy; it’s safer to include だ.
Is this sentence polite or casual? How do I make it polite?
As written it’s plain/casual. Polite versions:
- 締め切りを守るのは当然だと思います。
- More formal/businesslike: 締め切りは厳守すべきだと考えております。 or 締め切りを守るのは当然であると存じます。 (very formal)
Can I omit の or だ?
- Omitting の: Not here. You need の/こと to nominalize the verb phrase before は. Without it, 締め切りを守るは is ungrammatical. You could restructure to avoid の: 締め切りは守るのが当然だ.
- Omitting だ: Before と思う, keep だ with nouns/na-adjectives in standard speech: 当然だと思う.
Is 守る the right verb for “meet a deadline”? Any other options?
Yes. 締め切りを守る is the standard, natural way to say “meet/observe a deadline.” Alternatives:
- 締め切りを厳守する: “strictly observe the deadline” (formal/business).
- 締め切りに間に合わせる: “make it by the deadline” (focuses on finishing in time).
- For rules/policies: 〜を遵守する is formal “to comply with/observe” (e.g., 規則を遵守する). With deadlines, 期限を遵守する appears in formal writing.
What’s the difference between 締め切り and 期限? And how do I write 締め切り?
- 締め切り: a closing date/time for submissions, applications, etc.
- 期限: a time limit or due date by which something must be done/paid. Writing: You’ll see 締め切り, 締切, and sometimes 締切り. Modern style guides often prefer 締め切り (with the り in kana). Signage and forms may use the short 締切.
What is the overall grammar pattern of this sentence?
It’s the common pattern:
- [Verb-plain + の/こと] + は + [na-adjective + だ] + と + 思う Applied here: [締め切りを守る] の は [当然 だ] と 思う.
How do I express “should” or “must” instead of “it’s natural”?
- “Should/ought to”: 締め切りは守るべきだ（と思う）.
- “Have to/must”: 締め切りは守らなければならない／いけない; polite: 守らなければなりません. These are stronger than 当然だ, which frames it as an obvious expectation.
How do I negate this, and is there a difference between 〜だと思わない and 〜じゃないと思う?
Both exist, with a subtle difference in focus:
- 当然だと思わない: “I don’t think it is natural.” (negates the thinking)
- 当然じゃないと思う: “I think it isn’t natural.” (asserts the negative judgment) In everyday speech they’re often interchangeable; the second can sound a bit more assertive about the negative claim. Another careful option: 当然だとは思わない.
Do I need to say 私?
No. Japanese usually omits first-person pronouns when obvious. You can add it for clarity or contrast: 私は、締め切りを守るのは当然だと思う。 Using two は is fine here: first sets the speaker as topic, second sets the action as topic within that.
Can I change the word order?
The quoted clause must stay before と思う, but you can re-topic/reshuffle within reason:
- 締め切りを守るのが当然だと思う。 (uses が)
- 締め切りは守るのが当然だと思う。 (topicalizes deadlines)
- Polite: 私は、締め切りを守るのは当然だと思います。 Avoid splitting と思う from its quoted clause.
Is there a difference between 当然 and 当たり前 here?
Both mean “natural/obvious.” Nuance:
- 当然: slightly more formal/neutral; good in writing and polite contexts.
- 当たり前: more colloquial; can sound blunter or judgmental depending on tone. So 締め切りを守るのは当たり前だと思う is fine in casual speech; in business or neutral writing, 当然だ is safer.
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