tā kū de shíhou, péngyou yìzhí zài pángbiān ānwèi tā, shuō shìqíng huì mànmàn hǎoqǐlái.

的时候 means when or at the time when. It turns the earlier part into a time expression.

So:

• 她哭 = she cries / she is crying
• 她哭的时候 = when she cries / when she was crying

In this sentence, it sets the scene for what was happening at that time.

A very natural way to understand it is:

• 她哭的时候，朋友一直在旁边安慰她。
• When she was crying, her friend stayed by her side comforting her.

In V + 的时候, the 的 links the action to 时候.

This is a very common pattern:

• 吃饭的时候 = when eating / while eating
• 上课的时候 = when in class
• 回家的时候 = when going home

So 哭的时候 is not literally just cry time in a word-for-word English sense, but grammatically it means the time when someone is crying.

For learners, it is best to remember 的时候 as a chunk:

• …的时候 = when … / while …

Here 在 helps show an ongoing action, similar to be doing in English.

• 安慰她 = comfort her
• 在安慰她 = be comforting her

So:

• 朋友一直在旁边安慰她 means
• Her friend was continuously by her side comforting her

This 在 is not mainly about location here, even though 在 can also mean at/in/on in other sentences. In this sentence, it is part of the progressive idea: was comforting.

一直 means continuously, all along, or the whole time.

So:

• 朋友在旁边安慰她 = her friend was beside her comforting her
• 朋友一直在旁边安慰她 = her friend was beside her comforting her the whole time

It adds the idea that the action did not stop.

旁边 means beside, nearby, or at someone’s side.

In this sentence, 在旁边 suggests physical closeness:

• the friend stayed near her
• the friend was right there with her

So 一直在旁边安慰她 gives a strong feeling of emotional support: the friend was physically there, comforting her.

安慰她 means comfort her, and 她 is the object of the verb 安慰.

In Mandarin, if the object is important or needs to be clear, it is usually stated. So:

• 安慰她 = comfort her

If you removed 她, the sentence would just say comforted, without saying whom.

Sometimes Chinese can omit an object if it is obvious from context, but here keeping 她 sounds natural and clear.

It can mean either friend or friends, because Chinese nouns do not automatically show singular or plural the way English nouns do.

So 朋友 could mean:

• a friend
• friends

In this sentence, many learners will understand it as a friend, because the scene feels personal and focused. But grammar alone does not force it to be singular.

If you want to make it clearly plural, Chinese often adds context such as:

• 她的朋友们 = her friends

Yes. 说 means say, and what comes after it is the content of what was said.

So:

• 说事情会慢慢好起来 = saying that things would slowly get better

Chinese often does not need a word like that, and quotation marks are often omitted in ordinary writing when the meaning is clear.

So this part can be understood as:

• the friend said things will slowly get better

It works like reported speech or lightly marked direct speech.

The subject after 说 is omitted because it is already clear from context: it is the friend.

The sentence is understood like this:

• 她哭的时候，朋友一直在旁边安慰她，朋友说事情会慢慢好起来。

But repeating 朋友 would sound less natural. Chinese often omits a repeated subject when it is obvious.

So after 说, we naturally understand:

• the friend said...

Here 会 marks a future or expected development. It often means will.

So:

• 事情会好起来 = things will get better

In this sentence, 会 shows reassurance and expectation. The friend is saying that the situation is going to improve.

Be careful: 会 can also mean know how to in other sentences, but not here.

慢慢 means slowly or little by little.

So:

• 事情会好起来 = things will get better
• 事情会慢慢好起来 = things will slowly get better

It makes the statement softer and more realistic. It suggests improvement may take time, but it will happen.

好起来 means to get better, to improve, or to become well again.

This is different from just 好:

• 好 = good / well
• 好起来 = become good / start getting better

The 起来 here often shows a change starting to happen or becoming noticeable.

Common examples:

• 天气暖和起来了 = the weather has started to get warmer
• 身体好起来了 = the body/health has gotten better
• 事情会好起来 = things will get better

So 好起来 is about improvement, not just a static state.

It can be understood as things, the situation, or matters.

Chinese nouns do not always mark singular/plural clearly, so 事情 is flexible. In this sentence, it most naturally means:

• the situation
• things in general
• what’s going on

That is why the English translation often uses things.

Because the sentence is focused more on an ongoing scene and a general future outcome than on a completed event.

Look at the parts:

• 她哭的时候 sets the time background
• 一直在旁边安慰她 describes an ongoing action
• 事情会慢慢好起来 talks about future improvement

Since the sentence does not need to emphasize completion, 了 is not necessary.

If you added 了 in some places, the meaning or tone would change. For example:

• 她哭的时候，朋友一直在旁边安慰她。 focuses on the ongoing comforting

Adding 了 carelessly could make it sound more completed or shift the aspect in a way that is less natural for this sentence.

A helpful way to break it down is:

[Time clause] + [main action] + [what was said]

So:

• 她哭的时候 = when she was crying
• 朋友一直在旁边安慰她 = her friend was continuously by her side comforting her
• 说事情会慢慢好起来 = saying that things would slowly get better

So the full structure is:

• When she was crying, her friend stayed by her side comforting her, saying that things would slowly get better.

This is a very common Chinese way of building a sentence: first give the time or background, then the main action, then extra information such as speech or explanation.

Yes, it sounds natural and clear.

It has several very common spoken and written patterns:

• …的时候 for when...
• 一直在... for an ongoing action
• 在旁边 for being by someone’s side
• 说... to introduce what someone says
• 会慢慢好起来 for comforting reassurance

A native speaker might also say similar versions, such as:

• 她哭的时候，朋友一直陪在她旁边，安慰她说事情会慢慢好起来。
• 她哭的时候，朋友一直在她旁边安慰她，说一切都会慢慢好起来。

But your original sentence is already natural and correct.