kibun ga warukatta node gogo ha soutaisite, ie de atatakai otya wo nonde yasumimasita.

Because 悪かった is the past tense of the i-adjective 悪い.

• dictionary form: 悪い = bad
• past form: 悪かった = was bad

So:

• 気分が悪い = I feel sick / My condition is bad
• 気分が悪かった = I felt sick / My condition was bad

In i-adjectives, you usually make the past by changing -い to -かった:

• 寒い → 寒かった
• 高い → 高かった
• 悪い → 悪かった

ので means because or since.

In this sentence:

• 気分が悪かったので = because I felt sick

It connects the reason to the result:

• reason: 気分が悪かった
• result: 午後は早退して、家で温かいお茶を飲んで休みました

Compared with から, ので often sounds a little softer and more explanatory. It is very common when politely giving a reason.

So both of these are possible:

• 気分が悪かったので…
• 気分が悪かったから…

But ので often feels slightly more formal or gentle.

In 気分が悪い, the が marks 気分 as the thing that is in that condition.

So literally, it is something like:

• the feeling/condition was bad

This is a very common Japanese expression for feeling ill, feeling unwell, or feeling sick.

You can say 気分は悪かった in some contexts, but that would put more contrast or topic emphasis on 気分. For example, it could sound like:

• As for how I felt, it was bad
• or contrastive: My mood/condition was bad, but something else was fine

In a plain statement like this, 気分が悪かった is the natural choice.

午後 means afternoon.

The は marks it as the topic or sets the scene as “as for the afternoon”.

So:

• 午後は早退して… = In the afternoon, I left early…
• more literally: As for the afternoon, I left work/school early…

This は can also give a slight sense of contrast, depending on context. For example, it may suggest:

• maybe the morning was normal, but in the afternoon something different happened

Japanese often uses time expression + は this way.

早退する means to leave early from somewhere like:

• work
• school
• a meeting
• an activity

It usually means leaving before the normal finishing time, often because of illness or some other reason.

So:

• 早退して = left early and...

The して is the te-form of する, because 早退する is a suru-verb.

• dictionary form: 早退する
• te-form: 早退して
• past polite: 早退しました

In this sentence, 早退して links to the next action.

Because the sentence is listing actions in sequence.

Japanese often uses:

• Action 1 て、Action 2 て、Action 3 ました

Here the sequence is:

1. 早退して = left early
2. 家で温かいお茶を飲んで = drank warm tea at home
3. 休みました = rested

Only the final verb carries the main tense/politeness marking in this kind of structure.

So 早退して does not mean the action is unfinished. It simply connects it to what comes next.

Because で marks the place where an action happens.

Here, the actions are:

• 飲んで = drinking
• 休みました = rested

Those actions happened at home, so:

• 家で = at home

Compare:

• 家に帰る = go home
  
  • に marks destination
• 家で休む = rest at home
  
  • で marks location of action

So in this sentence, で is correct because the speaker is doing actions in that place.

Yes. In this sentence, the て-form links actions and usually suggests they happened in sequence.

• 温かいお茶を飲んで休みました = I drank warm tea and rested

The natural reading is:

1. drank warm tea
2. rested

The て-form often means:

• and
• then
• after doing that

The exact nuance depends on context, but a simple sequence is the most natural here.

Yes, the subject is omitted, which is very common in Japanese.

From context, we understand that the same person did all of these actions:

• felt sick
• left early
• drank tea
• rested

In English, we usually need to say I, but in Japanese, if the subject is obvious, it is often left out.

So the sentence naturally implies:

• I felt sick, so I left early in the afternoon, drank warm tea at home, and rested.

Japanese often avoids repeating subjects when the context already makes them clear.

温かい means warm.

So:

• 温かいお茶 = warm tea

This is a natural way to describe tea that is pleasantly warm. A learner may wonder about 熱い, which means hot, but 温かい often gives a softer, gentler feeling here—especially in a sentence about not feeling well.

So:

• 温かいお茶 sounds comforting
• 熱いお茶 would emphasize that it is hot

Both are possible in some contexts, but 温かいお茶 fits very naturally with resting at home when feeling sick.

A helpful way to break it up is:

• 気分が悪かったので
  because I felt sick
• 午後は早退して、
  I left early in the afternoon,
• 家で温かいお茶を飲んで
  drank warm tea at home,
• 休みました。
  and rested.

So the sentence has:

1. a reason clause with ので
2. a series of connected actions using the te-form
3. a final polite past verb: 休みました

This is a very common Japanese pattern:

• Reason + so/because
• Action 1 て
• Action 2 て
• Final action in past polite form

Yes, it is polite overall.

The final verb is:

• 休みました

This is the polite past form.

Even though earlier linked verbs appear as て-forms:

• 早退して
• 飲んで

the sentence is still polite because the final verb sets the tone of the sentence.

Also, ので sounds fairly polite and natural in explanatory speech.

So this is the kind of sentence you could say in a polite conversation, such as when explaining why you left early.