kibun ga warui hi wa gaishutsushimasen.

On days when I feel bad, I don't go out.

Breakdown of kibun ga warui hi wa gaishutsushimasen.

• は: topic particle
• が: subject particle
• 日ひ: day
• 悪わるい: bad
• 〜ません: negative polite form
• 外出がいしゅつする: to go out
• 気分きぶん: feeling; mood

Questions & Answers about kibun ga warui hi wa gaishutsushimasen.

What does 気分が悪い literally mean? Does it mean “in a bad mood”?

Literally, 気分 (kibun) = “feeling / condition / state,” and 悪い (warui) = “bad,” so 気分が悪い is “(my) condition/feeling is bad.”

In everyday usage, it usually means:

• physically unwell / feeling sick / nauseous, or
• just not feeling well (physically or overall).

If you want to clearly say “in a bad mood,” Japanese more often uses things like:

• 機嫌が悪い (kigen ga warui) = in a bad mood
  So 気分が悪い日 is closer to “days when I feel sick / unwell,” not “days when I’m grumpy.”

Why is it 気分が悪い and not 気分は悪い?

Here, 気分が悪い is part of a descriptive clause that modifies 日 (day):

• 気分が悪い日 = “days when (my) feeling is bad”

Inside a clause that modifies a noun, が is usually used to mark the subject of that clause:

• 気分が悪い日 ✅
• 気分は悪い日 ❌ (sounds wrong or at least very odd in this position)

You do use は when you’re making a main statement topic:

• 気分は悪いです。= As for my condition, it’s bad.

But in front of 日, this is a relative clause, so が is the natural choice.

How does 気分が悪い connect to 日? What’s the grammar here?

Japanese often puts a clause directly before a noun to describe it. That entire clause works like an adjective:

• 気分が悪い (feel sick) + 日 (day)
  → “day when (I) feel sick” / “sick-feeling day”

So:

• 気分が悪い日 = “days when I feel bad / unwell”

This is exactly like:

• 雨が降る日 = days when it rains
• 忙しい日 = busy days

Then the sentence is:

• 気分が悪い日は 外出しません。
  “On days when I feel unwell, I don’t go out.”

What is the role of は after 日 in 気分が悪い日は?

The は after 日 is the topic marker.
The topic here is:

• 気分が悪い日 = days when I feel unwell

So 気分が悪い日 + は means:

• “As for days when I feel unwell, (I don’t go out).”
• Natural English: “On days when I feel unwell, I don’t go out.”

The whole phrase 気分が悪い日 is being treated as the topic of the sentence.

Why use 日 (“day”) here? Could I say 気分が悪いときは外出しません instead?

Yes, you can say:

• 気分が悪いときは外出しません。

This means “When I feel unwell, I don’t go out.”
Nuance differences:

• 気分が悪い日 (days)
  Emphasizes days as units: on such days (those whole days), I stay in.

• 気分が悪いとき (when / at the time)
  Focuses more on times / moments when you feel unwell; it’s a bit more general.

Both are natural, but 日 makes it sound like you’re talking about whole days you classify as “bad-feeling days.”

Where is the subject “I” in this sentence? Who is not going out?

In Japanese, the subject (like “I,” “you,” “we”) is often omitted when it’s obvious from context.

Here:

• 気分が悪い日は外出しません。

Context tells us this is about the speaker:

• “On days when I feel unwell, I don’t go out.”

If you want to make it explicit, you can say:

• 私は気分が悪い日は外出しません。
  (Watashi wa kibun ga warui hi wa gaishutsu shimasen.)

But in natural conversation, Japanese usually drops 私 if it’s clear.

What does 外出しません literally mean? Is it different from 外に出ません?

外出 (がいしゅつ) is a noun meaning “going out / outing,” and します turns it into a verb: “to go out (from home, etc.).”
外出しません = “I don’t go out” (polite, somewhat neutral/formal).

You could also say:

• 外に出ません。 (soto ni demasen.)
  Literally: “I don’t go outside.”

Nuance:

• 外出しません: a bit more formal / neutral, suits writing and polite speech.
• 外に出ません: a bit more concrete and everyday, literally “don’t go out(side).”

Both are fine here; the meaning is very close.

Why is it 外出しません and not 外出しない? What’s the difference?

• 外出しません is the polite negative form.
• 外出しない is the plain (casual) negative form.

Meaning is the same: “don’t go out.”
You choose based on politeness:

• To a friend / diary / casual context:
  → 気分が悪い日は外出しない。

• To someone you’re polite with / in writing / in class examples:
  → 気分が悪い日は外出しません。

Does this sentence mean “I don’t go out today because I feel bad right now,” or is it more general?

気分が悪い日は外出しません。 is a general / habitual statement:

• “On days when I feel unwell, I (generally) don’t go out.”
• It describes your usual rule or habit, not just today.

If you wanted to state it just about today, you’d usually be more specific, e.g.:

• 今日は気分が悪いので外出しません。
  “I’m not going out today because I feel unwell.”

What’s the difference between 気分が悪い, 具合が悪い, and 気持ちが悪い?

They’re all related but have different common uses:

1. 気分が悪い (kibun ga warui)

   • “My condition/feeling is bad.”
   • Often used for feeling unwell overall; can include nausea, dizziness, general sickness.

2. 具合が悪い (guai ga warui)

   • VERY common for “I don’t feel well / I’m sick.”
   • Sounds clearly physical condition: headache, cold, stomach ache, etc.

3. 気持ちが悪い (kimochi ga warui)

   • Literally “feeling is bad,” but in practice often:
     • “I feel sick / nauseous” or
     • “That’s gross / creepy / disgusting.”
   • E.g. 虫が気持ち悪い = “Bugs are gross.”

In your sentence, 気分が悪い日 is fine; 具合が悪い日 would also sound natural if you mean clearly physical illness.

Could I say this as an “if” sentence, like “If I feel unwell, I don’t go out”?

Yes. A common pattern is to use と or たら:

• 気分が悪いと外出しません。
  “If I feel unwell, I don’t go out.” (general rule)

• 気分が悪かったら外出しません。
  Literally “If (I) feel/felt bad, I won’t go out”
  → Used a bit more in actual decision-making situations.

Your original:

• 気分が悪い日は外出しません。

is very close in meaning to 気分が悪いと外出しません, but it emphasizes “on such days” rather than the condition “if.”