mousikomisyo ha kyouzyuu ni dasimasu.

A natural reading is:

申込書は今日中に出します。
もうしこみしょ は きょうじゅう に だします。

Word readings:

• 申込書 = もうしこみしょ = application form
• 今日中 = きょうじゅう = by the end of today / sometime before today is over
• 出します = だします = will submit / hand in

は marks the topic of the sentence.

So 申込書は means something like:

• As for the application form, ...
• About the application form, ...

This makes 申込書 the thing the speaker is talking about.

In English, we do not usually mark the topic this clearly, so this can feel unusual at first.

It can be 申込書を今日中に出します, and that would be very natural too.

The difference is:

• 申込書を今日中に出します
  Focuses more directly on the object being submitted.

• 申込書は今日中に出します
  Sets the application form up as the topic, often with a nuance like:

  • As for the application form, I’ll submit it today
  • possibly contrasting it with something else

For example, it can sound like:

• The application form, I’ll submit today, but something else maybe later

So は can add a mild contrast or topical feel, while を is a straightforward object marker.

今日中 means within today or by the end of today.

It does not just mean today in a general sense. It specifically gives a deadline:

• before today is over
• by tonight
• by the end of the day

So it is stronger and more precise than just 今日.

Compare:

• 今日出します = I’ll submit it today
• 今日中に出します = I’ll submit it by the end of today

Here, に marks the time limit / target point for the action.

So 今日中に means:

• by the end of today
• within today

You can think of it as marking the point that the action must be completed by.

This に is common with expressions that function like deadlines or points in time.

Yes, 出す has several meanings, and submit / hand in is one of them.

Common meanings of 出す include:

• take out
• put out
• send
• submit / hand in

In the case of documents like 申込書, 出す often means:

• submit
• hand in
• turn in

So in this sentence, 出します does not mean physically taking the form out somewhere. It means submitting it.

Japanese often leaves out the subject when it is understood from context.

So 申込書は今日中に出します most naturally means:

• I will submit the application form by the end of today

But depending on context, it could also mean:

• We will submit it
• He/she will submit it

In real conversation, the listener usually figures this out from the situation.

出します is the polite non-past form of 出す.

Here it usually means:

• will submit
• or sometimes submit in a polite statement

Related forms:

• dictionary form: 出す
• polite form: 出します
• past polite: 出しました
• negative polite: 出しません

So this sentence is polite and appropriate in normal conversation, work situations, and many everyday contexts.

Japanese normally puts the main verb at the end of the sentence.

So the structure here is:

• 申込書は = topic
• 今日中に = time limit
• 出します = verb

This is very normal Japanese word order.

English speakers often expect the verb earlier, but in Japanese the verb usually comes last.

Yes, some parts can move around, as long as the sentence still sounds natural.

For example:

• 申込書は今日中に出します
• 今日中に申込書は出します

Both are possible.

However, changing the order can slightly change the emphasis. Japanese word order is more flexible than English, but it is not completely free. The most neutral version here is probably:

申込書は今日中に出します。

By itself, 申込書 does not clearly show singular or plural.

It could mean:

• the application form
• an application form
• application forms

The exact number depends on context.

Japanese often leaves number unspecified unless it is important.

Sometimes, yes.

Using は instead of を can suggest a contrast such as:

• The application form, I’ll submit today
• maybe but something else I won’t
• or that one at least will be done today

This contrast may be very weak, and sometimes it is just topical rather than strongly contrastive. The exact nuance depends on context and intonation.

So は does not always mean a strong contrast, but learners should know that it can carry that feeling.