uketorinin no zyuusyo wo matigaetara, kodutumi ga todokanai kamo siremasen.

It is read うけとりにん.

• 受け取る / 受取る = to receive
• 人 = person

So 受取人 literally means the person who receives it, i.e. the recipient.

In this sentence, it means the person who is supposed to receive the package.

の connects two nouns.

Here, 受取人の住所 means:

• 受取人 = recipient
• 住所 = address

So together it means the recipient’s address or the address of the recipient.

This is a very common use of の:

• 私の本 = my book
• 学校の先生 = the school’s teacher / teacher at the school
• 日本の文化 = Japanese culture

Because 住所 is the direct object of 間違える.

The structure is:

• 住所を間違える = to make a mistake with the address / to get the address wrong

So を marks the thing that is mistaken.

Even though English says make a mistake in the address or get the address wrong, Japanese treats address as the object of the verb:

• 名前を間違える = get the name wrong
• 番号を間違える = get the number wrong

間違えたら is the -たら conditional form of 間違える.

Breakdown:

• 間違える = to make a mistake / get something wrong
• 間違えた = made a mistake / got it wrong
• 間違えたら = if you make a mistake / if you get it wrong

So 住所を間違えたら means: if you get the address wrong.

The -たら form is commonly used for if/when conditions.

Examples:

• 雨が降ったら、行きません。 = If it rains, I won’t go.
• 時間があったら、手伝います。 = If I have time, I’ll help.

Because 間違える is typically the transitive verb, meaning to get something wrong.

• 間違える = to mistake something, to get something wrong
• 間違う = to be mistaken, to make a mistake

In this sentence, there is a specific thing being gotten wrong: 住所. That makes 間違える a natural choice.

Compare:

• 住所を間違えた。 = I got the address wrong.
• 私は間違った。 = I was mistaken / I made a mistake.

In everyday Japanese, the distinction is not always perfectly strict in all contexts, but for learners, this is a good basic way to understand it.

Because 届く is an intransitive verb.

• 届く = to arrive, to be delivered, to reach
• It does not take a direct object with を

So 小包が届かない means: the package does not arrive / the package may not be delivered

Here, 小包 is the subject of 届く, so it takes が.

Compare:

• 荷物が届く = the package arrives
• 手紙が届く = the letter arrives

Japanese often describes this situation from the point of view of the item arriving rather than someone delivering it.

So:

• 小包が届く = the package arrives / is delivered

In English, we might naturally think of the postal service delivering it, but Japanese often focuses on the result: Did it reach the recipient or not?

If you wanted to talk about delivering something as an action done by a person, you would use a different verb, such as 届ける:

• 郵便屋さんが小包を届ける = the mail carrier delivers the package

But in this sentence, the point is whether the package reaches the destination, so 届く is the right verb.

かもしれません means may, might, or it is possible that.

So:

• 届かないかもしれません = it might not arrive

This expression softens the statement and makes it less certain.

Compare:

• 届きません。 = It will not arrive.
  Stronger, more direct.
• 届かないかもしれません。 = It may not arrive.
  Less certain, more cautious.

This is a very common expression in Japanese.

Because the uncertainty applies to the negative idea: not arriving.

• 届く = arrive
• 届かない = not arrive
• 届かないかもしれません = might not arrive

So the speaker is saying: If the recipient’s address is wrong, there is a possibility that the package will not arrive.

If you said 届くかもしれません, that would mean: it might arrive, which gives the opposite possibility.

Yes, it is polite/formal.

Compare:

• かもしれない = plain form
• かもしれません = polite form

So:

• 届かないかもしれない。 = It might not arrive.
  Casual/plain.
• 届かないかもしれません。 = It might not arrive.
  Polite.

This sentence sounds like something you might hear in customer service, instructions, or a polite explanation.

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

住所を間違えたら literally just says: if [someone] gets the address wrong

In context, it usually means:

• if you get the recipient’s address wrong
• or more generally if the address is written incorrectly

Japanese often leaves out subjects when they are understood from context.

A natural reading is:

うけとりにん の じゅうしょ を まちがえたら、こづつみ が とどかない かも しれません。

Without the learner-style spaces, it is usually written as:

受取人の住所を間違えたら、小包が届かないかもしれません。

Right. Normal Japanese is usually written without spaces.

So standard writing would be:

受取人の住所を間違えたら、小包が届かないかもしれません。

The spaces here are just for learners, to make the parts easier to see:

• 受取人
• の
• 住所
• を
• 間違えたら
• 小包
• が
• 届かない
• かも
• しれません

Also, かもしれません is normally written as one unit, not split into かも しれません in everyday writing.

Here, たら is best understood as if.

The sentence expresses a condition and a possible result:

• If the recipient’s address is wrong,
• the package might not arrive.

Sometimes たら can also mean when/after, depending on context, but in this sentence it clearly expresses a conditional situation.

So the nuance is: in the event that the address is mistaken, this bad result may happen.