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Questions & Answers about kyou ha samui desu.
What does は do in 今日は寒いです?
は is the topic marker. It tells the listener that you’re talking about 今日 (“today”) as the general topic. Literally it’s like saying, “As for today, (it) is cold.” Note that although it’s written as は, it’s pronounced wa when used as a particle.
Why is the subject (like “it” or “the weather”) omitted?
In Japanese, if the subject is obvious from context, you usually drop it. Here everyone understands you’re talking about the weather or “it” in general, so you don’t need to say それ or 天気. English forces you to say “It is cold,” but Japanese lets you skip that.
What role does です play here? And can it be dropped?
です is the polite ending (the copula) that makes the sentence more formal. With an i-adjective like 寒い, adding です doesn’t change the meaning—it just raises the politeness level. In casual speech you can drop です and simply say 今日は寒い.
What kind of adjective is 寒い, and how does it conjugate?
寒い is an i-adjective (形容詞). You can tell because it ends in い and conjugates without だ/です. For example:
- Past tense (polite): 寒かったです
- Past tense (casual): 寒かった
- Negative (polite): 寒くないです
- Negative (casual): 寒くない
How do you say “It was cold today” politely and casually?
Polite: 今日は寒かったです
Casual: 今日は寒かった
When would you use が instead of は in a sentence like this?
You use が to mark new or specific subjects, not topics. Here は is correct because you’re stating something about today (a known topic). If you wanted to answer “What is cold?” you could ask 何が寒いですか？ and then answer 今日は寒いです, but you wouldn’t replace は with が in the original sentence.
Why is 今日 read as きょう and not こんにち?
Although the kanji 今日 can be read こんにち in very formal compounds (e.g. 今日現在), the everyday reading for “today” is きょう. The greeting こんにちは actually comes from 今日は plus the particle は, but as a set phrase it’s pronounced konnichi-wa and usually written in hiragana.
How can I soften or add nuance to this sentence?
You can add sentence-ending particles:
- 今日は寒いですね。
(seeking confirmation: “It’s cold today, isn’t it?”) - 今日は寒いよ。
(casual, adding emphasis: “Hey, it’s cold today!”) - 今日はけっこう寒いです。
(adding けっこう “pretty/quite” for nuance: “It’s pretty cold today.”)