zhèjiā diàn de rén hěn yǒulǐmào, yí jìnmén jiù xiào zhe gēn wǒmen shuō “nǐhǎo".

In this sentence, 这家店的人 most naturally means the people who work at this store, especially the staff.

Breakdown:

• 这家店 = this shop / this store
• 的人 = the people of / the people associated with

So it does not usually mean random customers in the shop. It refers to the people belonging to or working for the store.

家 is a measure word often used for businesses and establishments.

So:

• 这家店 = this shop
• 那家公司 = that company
• 一家饭馆 = a restaurant

You cannot normally just say 这店 in standard Mandarin when you want to say this shop in a natural, complete way. The measure word 家 makes it sound normal and grammatical.

Here, 的 links a noun phrase to another noun, a bit like of or a possessive marker in English.

• 店的人 = the store’s people / the people from the store

It shows that 人 is connected to 店.

Compare:

• 学校的人 = people from the school
• 公司的人 = people from the company

So 的 is marking a relationship between the store and the people.

Not always. In Chinese, 很 is often used before adjectives or adjective-like expressions even when the speaker does not strongly mean very.

So:

• 很有礼貌 can mean very polite
• but in many contexts it simply means polite

This happens because Chinese often prefers a degree word before an adjective in a plain statement.

Compare:

• 他很高 = He is tall
  Not necessarily very tall

So here 很有礼貌 is often just a natural way to say the staff are polite.

Literally, 有礼貌 means to have manners / to be polite.

Structure:

• 有 = have
• 礼貌 = politeness / manners

Even though it literally contains the verb 有, the whole expression functions much like an adjective in many sentences.

For example:

• 他很有礼貌 = He is polite
• 那个孩子真有礼貌 = That child is really polite

So it is best to learn 有礼貌 as a set expression meaning polite.

This is because of tone sandhi.

Normally:

• 一 is first tone: yī

But its pronunciation changes depending on the tone that follows:

• before a 4th-tone syllable, it becomes yí
• before a 1st, 2nd, or 3rd-tone syllable, it becomes yì
• when said alone or emphasized, it stays yī

Here:

• 进 is 4th tone (jìn)

So:

• 一进门 is pronounced yí jìnmén

一……就…… means as soon as... then... or once... immediately...

In this sentence:

• 一进门 = as soon as they entered / upon entering
• 就笑着跟我们说 = they immediately, smiling, said to us...

So the pattern emphasizes that the second action happens right after the first one.

Other examples:

• 一到家就睡觉 = As soon as I get home, I go to sleep.
• 他一看见我就笑了 = As soon as he saw me, he smiled.

Yes, the subject is omitted, but it is understood from the previous part of the sentence.

Earlier, the sentence mentions:

• 这家店的人很有礼貌

So in the next part, the subject is still the people in the store / the staff.

Chinese often leaves out subjects when they are already clear from context. English usually repeats them more often, but Chinese does not need to.

So the full idea is:

• 这家店的人很有礼貌，(他们)一进门就笑着跟我们说……

Here, 着 shows a continuing state or accompanying action.

So 笑着跟我们说 means:

• speaking to us while smiling
• or smilingly said to us

It connects the two actions:

• 笑 = smile
• 说 = speak / say

The idea is that the smiling is happening at the same time as the speaking.

Compare:

• 站着说话 = speak while standing
• 看着我说 = say it while looking at me

So 着 often means while doing or in the state of doing.

Yes, 对我们说 would also be possible.

Both can mean say to us, but there is a slight difference in feel:

• 跟我们说 is very common in everyday spoken Mandarin and can feel more conversational.
• 对我们说 focuses a bit more on the direction/target of the speech.

In this sentence, 跟我们说 sounds natural and friendly, which fits a store greeting.

Compare:

• 他跟我说了一句话。 = He said something to me.
• 他对我说了一句话。 = He said something to me.

Both are correct; the difference is small here.

Good question. In real Mandarin, 你好 is often used as a general greeting even when more than one person is being addressed, especially in service situations.

So a shop worker may say:

• 你好

even to a pair or a group of customers.

你们好 is grammatically correct and can be used, but in everyday greetings it is less common than learners sometimes expect. 你好 often works as a fixed greeting formula.

Yes. 进门 literally means enter the door, but in natural English it often corresponds to:

• come in
• enter
• walk in

Its exact translation depends on context.

For example:

• 他刚进门。 = He just came in.
• 一进门就看见她。 = As soon as I walked in, I saw her.

So it is a very common expression for entering a place.

Yes. The sentence has two connected parts:

1. 这家店的人很有礼貌
2. 一进门就笑着跟我们说“你好”

The first part gives a general statement: the staff are polite.
The second part gives evidence or an example of that politeness: as soon as someone comes in, they smile and say hello.

This kind of structure is very common in Chinese:

• statement first
• supporting action or explanation after

So the comma helps separate the general description from the example that follows.