ninki no mise no mae ni gyouretu ga dekite ita node, betu no mise ni ikimasita.

人気 is a noun that means popularity or being popular.

So:

• 人気の店 = a popular shop / restaurant
• literally, a shop of popularity

In Japanese, a noun can modify another noun with の, so 人気の店 is a very natural way to say a popular shop.

A related expression is:

• 人気がある店 = a shop that is popular

Both are natural, but 人気の店 is more compact.

Each の links one noun to the next.

Break it down like this:

• 人気の店 = popular shop
• 店の前 = in front of the shop

Put them together:

• 人気の店の前 = in front of the popular shop

So the structure is:

• 人気 → modifies 店
• 店 → modifies 前

This kind of noun chaining is very common in Japanese.

Yes, 前 can mean either:

• in front of (place)
• before (time)

Here it is clearly the place meaning, because it follows 店の:

• 店の前 = in front of the shop

So:

• 人気の店の前に = in front of the popular shop

If it were a time meaning, the context would be different, such as:

• 食事の前に = before the meal

に marks the place where something exists or happens.

In this sentence, the thing that happens is:

• 行列ができていた = a line had formed / there was a line

That line formed in front of the shop, so Japanese marks that location with に:

• 店の前に行列ができていた

You can think of it as:

• At/In front of the shop, a line had formed

Very literally, it is something like:

• A line had come into existence
• A queue had formed

Breakdown:

• 行列 = line, queue
• が = subject marker
• できる = to be made / to be formed / to come into being
• できていた = past ている form

In natural English, this usually becomes:

• there was a line
• a line had formed
• people were lined up

Because できる here is intransitive.

That means the line is not a direct object being actively made by someone. Instead, the line comes into being or forms.

So:

• 行列ができる = a line forms
• not 行列をできる

The sentence is focusing on the result/state: a queue existed there.

Good question. ていた often gives a sense of an ongoing state or a resulting condition in the past.

Compare:

• 行列ができた = a line formed
• 行列ができていた = a line had formed / there was a line there

In this sentence, できていた suggests that when the speaker got there or noticed the place, the line was already present.

So it is less about the single event of formation and more about the visible situation:

• there was already a line in front of the popular shop

が marks 行列 as the thing that exists/appears/forms.

With できる, が is very common because it marks what came into being:

• 行列ができる = a line forms

If you used は, the nuance would shift more toward contrast or topic marking. But in a normal statement describing what was there, が is the natural choice.

So here, が simply identifies the queue as the subject of できていた.

Both ので and から can mean because, but the nuance is a little different.

• ので sounds a bit softer, more explanatory, and often more neutral
• から can sound more direct or more like the speaker’s personal reason

So:

• 行列ができていたので、別の店に行きました。 = Because there was a line, I went to a different shop.

This sounds like a calm explanation of what happened.

If you used から, it would still be correct, but slightly more direct:

• 行列ができていたから、別の店に行きました。

別の means another or different.

So:

• 別の店 = another shop / a different shop

It implies the speaker chose a shop different from the popular one.

This is a very common pattern:

• 別の方法 = a different method
• 別の日 = another day
• 別の人 = a different person

When 別 directly modifies a noun, it is commonly used as 別の + noun.

So:

• 別の店 = correct and natural

You can sometimes see 別 used in other structures, but before a noun, 別の is the standard form learners should remember.

Because the sentence is narrating a completed action in the past.

The sequence is:

1. There was a line in front of the popular shop.
2. Because of that, the speaker went to another shop.

So:

• 行きました = went

It matches the past situation described by できていた.

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

So this sentence does not explicitly say I, we, or they. In many everyday contexts, the listener understands it from the situation.

Depending on context, it could mean:

• I went to another shop
• we went to another shop
• less commonly, he/she/they went to another shop

If this is a standalone example, English usually supplies I as the most natural interpretation.

店 literally means shop/store, but in context it can refer to many kinds of businesses, including a place to eat.

Because the sentence mentions a queue and then going to another place, it could very naturally be:

• a restaurant
• a café
• a shop/store

So English translation depends on context. Japanese 店 is broader than just one English word.

Yes, that is a very natural translation.

Even though the Japanese literally says something more like a line had formed, natural English often prefers:

• There was a line in front of the popular shop
• There was a queue in front of the popular shop
• People were lined up in front of the popular shop

All of these capture the meaning well.