Tā yòng xīn shǒujī de shíhou, xiān dēnglù zìjǐ de zhànghào, ránhòu kàn lǐmiàn de xiāoxi.

In Chinese, 的时候 is often added after a word, phrase, or clause to mean when or at the time that.

So here:

• 用新手机 = use a new phone
• 用新手机的时候 = when using a new phone / when she uses a new phone

You can think of it as:

• [action/event] + 的时候

This is a very common pattern in Mandarin.

的时候 means when, while, or at the time of.

In this sentence, it introduces the time situation for the main actions:

• 她用新手机的时候 = when she uses a new phone
• then the main clause tells us what she does at that time:
  • 先登录自己的账号
  • 然后看里面的消息

So 的时候 sets the scene, and the rest tells what happens during that time.

That 的 is part of the fixed pattern 的时候.

It links the earlier phrase to 时候:

• 用新手机 = use a new phone
• 用新手机的时候 = the time when she uses a new phone

This is not the same as the 的 used just to show possession, although it looks identical. Chinese 的 has several related grammar functions, and this is one of them.

Each 的 is doing a slightly different job:

1. 用新手机的时候

   • the 的 links the action phrase to 时候
   • when using a new phone

2. 自己的账号

   • the 的 links 自己 to 账号
   • one’s own account

3. 里面的消息

   • the 的 links 里面 to 消息
   • the messages inside

So even though they all look the same, they are all serving the general linking/modifying function that 的 often has in Chinese.

先 means first, and in Chinese it usually goes directly before the verb or verb phrase it modifies.

So:

• 先登录自己的账号 = first log into her own account

This is very natural Chinese word order:

• 先 + verb
• 然后 + verb

So the sequence is:

• 先登录...
• 然后看...

That is the standard way to show order of actions.

先...然后... means first... then...

It is one of the most common ways to describe a sequence in Chinese.

In this sentence:

• 先登录自己的账号
• 然后看里面的消息

So the order is:

1. first log into her account
2. then look at/read the messages inside

You can use this pattern with many actions, for example:

• 先吃饭，然后学习。
  • First eat, then study.

自己 means oneself / one’s own, and it often refers back to the subject of the sentence.

So here:

• 她 is the subject
• 自己的账号 means her own account

Using 自己 makes it especially clear that the account belongs to the same person who is doing the action.

Compare:

• 她的账号 = her account
• 自己的账号 = her own account

In many contexts, 自己的 sounds more natural when the owner is the same as the subject.

Yes, it could, but the nuance is a little different.

• 她的账号 simply means her account
• 自己的账号 emphasizes her own account

In this sentence, 自己的账号 is a very natural choice because it highlights that she logs into the account that belongs to herself, not someone else’s.

For a learner, a useful rule is:

• if the owner is the same as the subject, 自己(的) is often a good choice

登录 means to log in or to sign in.

Chinese often does not need a separate word like English into in this kind of sentence. The verb itself already carries the meaning of logging in.

So:

• 登录账号 = log into an account
• more literally: log in account, but natural English becomes log into an account

Chinese and English package this idea differently. This is very normal.

里面 means inside or in there.

So:

• 里面的消息 = the messages inside

What inside refers to depends on context. In this sentence, it most naturally means the messages inside the account, app, phone, or system she has just logged into.

Chinese often leaves this kind of reference slightly implicit when it is obvious from context.

Here, 的 links the location word 里面 to the noun 消息.

• 里面 = inside
• 里面的消息 = the messages inside / the messages in there

This is a common pattern:

• 桌子上的书 = the book(s) on the table
• 房间里的东西 = the things in the room
• 里面的消息 = the messages inside

So X 的 Y often means the Y that is in/on/related to X.

In this context, 看消息 usually means read/check the messages, not just physically look at them.

Chinese 看 is very broad. Depending on context, it can mean:

• look at
• watch
• read
• check

So here, natural English would usually be:

• check the messages
• read the messages

rather than a literal look at the messages.

Because this sentence is describing a general sequence or routine, not emphasizing completion of a specific past event.

Without 了, the sentence can sound more like:

• a general habit
• a usual procedure
• a plain description of what happens

If you added 了, the sentence would sound more tied to a specific completed event in context.

For example, this sentence as written is like:

• When she uses a new phone, she first logs into her own account, then checks the messages inside.

It sounds procedural or habitual.

Because the sentence is not counting the phone.

Chinese classifiers are required in patterns like:

• 一部手机 = one phone
• 这部手机 = this phone

But here, 新手机 is just a noun phrase meaning new phone, not one new phone or this new phone. So no classifier is needed.

This is similar to English:

• a new phone = counting
• new phone use / using a new phone = not necessarily focused on counting

It can mean either, depending on context.

新手机 literally means new phone, but Chinese does not always spell out whether it is:

• newly purchased / brand-new, or
• just newly obtained / new to the user

In this sentence, both are possible. Since she logs into her account and then checks messages, it often suggests a phone that is newly being set up or newly being used.

Because once the subject is established, Chinese often does not repeat it unnecessarily.

The sentence is structured like this:

• 她用新手机的时候
• 先登录自己的账号
• 然后看里面的消息

Both 登录 and 看 are still understood to have 她 as the subject.

Chinese often prefers this kind of smooth, topic-based flow instead of repeating pronouns the way English sometimes does.

Yes. You could say:

• 她在用新手机的时候，先登录自己的账号，然后看里面的消息。

That is grammatical. But in many cases, the shorter version without 在 is perfectly natural:

• 她用新手机的时候...

Adding 在 can sometimes make the timing feel a little more explicitly framed, but it is not required here.

Yes, it helps show the structure.

The first part:

• 她用新手机的时候

is the time-setting phrase: when she uses a new phone

Then the main actions come after it:

• 先登录自己的账号
• 然后看里面的消息

The comma makes that boundary clearer, just like in English:

• When she uses a new phone, she first logs into her own account, then checks the messages inside.

So the comma is very natural and helpful.