asita ha yasumi desu kara, kyouzyuu ni sigoto wo katadukemasu.

は marks 明日 as the topic: As for tomorrow, ...

In this sentence, 明日は休みです means something like:

• Tomorrow is a day off
• more literally, As for tomorrow, it is a day off

Using は here gives a natural topic-comment structure. You could think of it as setting the scene before giving the reason for the main action.

Here, 休み is a noun.

So:

• 休みです = is a holiday / is a day off / is a break

It is not an -i adjective.
This is why it uses です directly, like a noun sentence.

Examples:

• 今日は休みです。 = Today is a day off.
• 日曜日は休みです。 = Sunday is a day off.

Yes. から can follow a plain statement to mean because / since.

So:

• 休みです = it is a day off
• 休みですから = because it is a day off

This is very common in polite speech.

Compare:

• plain: 休みだから
• polite: 休みですから

Both mean because it’s a day off, but ですから matches the polite style of the sentence.

今日中に means by the end of today or sometime before today is over.

Breakdown:

• 今日 = today
• 中 = inside / within
• 今日中 = within today
• 今日中に = by sometime within today

It does not just mean today in a general sense. It emphasizes a deadline.

So the nuance is:

• not just I’ll do it today
• but I’ll finish it before today ends

Here に marks the time limit / target point.

So 今日中に means:

• by today
• within today
• before today ends

This is similar to how に can mark a specific time or deadline.

Examples:

• 五時までに帰ります。 = I’ll return by 5:00.
• 今日中に終わらせます。 = I’ll finish it by the end of today.

を marks the direct object of the verb.

The verb here is 片付けます, and the thing being dealt with is 仕事.

So:

• 仕事を片付けます = I will take care of the work / finish up the work

In other words, 仕事 is what gets 片付けられる.

Often, yes—but it has a broader meaning than just physically cleaning.

片付ける can mean:

• to tidy up
• to put away
• to deal with
• to finish off
• to clear up

With 仕事, it often means:

• to get work done
• to clear up pending work
• to wrap up work

So in this sentence, it does not mean physically cleaning the job. It means finishing or taking care of the work.

In Japanese, the non-past form covers both:

• present/habitual actions
• future actions

So 片付けます can mean:

• I tidy up
• I will tidy up
• I will finish up

Here, because of the context, it clearly refers to the future:

• Tomorrow is a day off, so I’ll finish the work by today.

Japanese often relies on context rather than a special future tense.

Japanese often leaves out subjects and possessives when they are obvious from context.

So even though English would usually say:

• I’ll finish my work by today

Japanese can simply say:

• 今日中に仕事を片付けます

The listener naturally understands that the speaker means I and probably my work or the work I need to do.

This omission is extremely common in Japanese.

Yes, and the meaning would stay very similar:

• 明日は休みですから、今日中に仕事を片付けます。
• 明日は休みなので、今日中に仕事を片付けます。

Both mean Because tomorrow is a day off, I’ll finish the work by today.

General nuance:

• から can sound a little more direct or speaker-based
• ので can sound a bit softer or more explanatory

In everyday conversation, both are natural.

Yes. Japanese often puts the reason first, but you can also put the main statement first.

For example:

• 今日中に仕事を片付けます。明日は休みですから。

This is also natural, especially in speech. It feels a bit like:

• I’ll finish the work by today. After all, tomorrow is a day off.

The original version is smoother as one complete sentence, but both are possible.

It depends on context.

休みです can mean:

• I’m off tomorrow
• Tomorrow is a holiday
• The office/school is closed tomorrow

By itself, Japanese often leaves this kind of thing vague if the listener can infer it.

In this sentence, because the speaker says they will finish work today, it strongly suggests:

• the speaker will not be working tomorrow, or
• tomorrow is a non-working day for them

It is basically:

[Reason] から, [main action].

Breakdown:

• 明日は休みですから = Because tomorrow is a day off
• 今日中に仕事を片付けます = I will finish the work by the end of today

So the full structure is:

• Because X, I will do Y.

This is a very common Japanese sentence pattern.