jigeumeun jeomsimsiganiraseo sikdange sarami manhayo.

A simple breakdown is:

• 지금은 = as for now / right now
• 점심시간이라서 = because it is lunchtime
• 식당에 = in/at the restaurant
• 사람이 많아요 = there are many people / people are many

So the sentence is structured like:

time/topic + reason + location + subject + descriptive verb

A very literal gloss would be something like:

As for now, because it is lunchtime, at the restaurant people are many.

That sounds unnatural in English, but it matches the Korean grammar more closely.

은 is the topic particle. In 지금은, it makes 지금 the time frame or topic of the sentence:

• 지금은 = as for now / right now
• it can imply contrast, like right now (at least), maybe different from earlier or later

Without 은, 지금 would still mean now, but 지금은 sounds a little more like setting the scene.

For example:

• 지금 사람이 많아요. = There are a lot of people now.
• 지금은 사람이 많아요. = As for now, there are a lot of people.

In English, this difference is often very subtle or not translated directly.

-이라서 means because it is... when it attaches to a noun.

Here:

• 점심시간 = lunchtime
• 점심시간이라서 = because it is lunchtime

This is a very common way to give a reason.

A useful pattern is:

• noun + 이라서 after a noun ending in a consonant
• noun + 라서 after a noun ending in a vowel

Examples:

• 학생이라서 = because (someone) is a student
• 휴일이라서 = because it is a holiday
• 학교라서 = because it is a school

So in your sentence, 점심시간이라서 explains why the restaurant has many people.

Yes. 점심시간이어서 is also possible.

Both mean because it is lunchtime, but -이라서/-라서 is extremely common in everyday speech and often feels very natural and direct.

So:

• 점심시간이라서 식당에 사람이 많아요.
• 점심시간이어서 식당에 사람이 많아요.

Both are correct.

For a learner, the important thing is to recognize -이라서 / -이어서 as reason forms after nouns.

This is a very common question.

Here, 에 marks the place where something exists or is located. The sentence is describing the state of the restaurant: there are many people there.

So:

• 식당에 사람이 많아요 = There are many people in the restaurant.

에서 is usually used for the place where an action happens:

• 식당에서 먹어요. = I eat at the restaurant.

Because 많아요 is not an action like eating, 에 is the natural choice here.

A good way to remember it:

• 에 = location of existence/state
• 에서 = location of action

Because 이/가 marks 사람 as the subject of 많아요.

In this sentence, the thing that is many is people, so 사람이 is the normal form:

• 사람이 많아요 = people are many / there are many people

If you said 사람은 많아요, it would sound more contrastive, like:

• As for people, there are many...
  maybe implying something else is not abundant

So 사람이 많아요 is the neutral, natural choice here.

In Korean, nouns often do not need a plural marker even when they refer to multiple things.

So:

• 사람이 많아요 already means there are many people
• you do not need 들 to show plurality here

사람들 is possible, but it adds extra emphasis on the plural group and is often unnecessary.

This is very normal in Korean:

• 학생이 많아요 = there are many students
• 차가 많아요 = there are many cars
• 사람이 많아요 = there are many people

So the singular-looking form 사람 can still refer to people in general or multiple people.

It is a descriptive verb, which is often called an adjective in beginner materials.

Its dictionary form is 많다, meaning to be many / to be much.

So Korean does not need a separate expression like there are in the same way English does. Instead, it says something closer to:

• people are many
• the number of people is large

That is why 사람이 많아요 is the natural Korean way to say there are many people.

Because Korean often describes the situation more directly as there are many people in the restaurant.

So:

• 식당에 사람이 많아요 literally focuses on many people being in the restaurant
• in natural English, that can often be translated as the restaurant is crowded

But grammatically, the Korean sentence is not saying crowded as a separate adjective. It is specifically saying there are many people.

That distinction is useful, because Korean often expresses ideas through number or presence rather than the exact adjective English might choose.

많아요 is in the polite present style, which is very common in everyday conversation.

Related forms:

• 많다 = dictionary form
• 많아요 = polite
• 많아 = casual/intimate
• 많습니다 = formal polite

So this sentence sounds polite and natural for ordinary conversation, class examples, and many real-life situations.

Yes, Korean word order is somewhat flexible, but some parts still sound more natural in certain positions.

This sentence is very natural as:

• 지금은 점심시간이라서 식당에 사람이 많아요.

You could also say:

• 식당에 사람이 많아요. 지금은 점심시간이라서요.
• 지금은 식당에 사람이 많아요. 점심시간이라서요.

But the original sentence flows well because it gives:

1. the time/topic
2. the reason
3. the main statement

That order is very common in Korean.

Yes.

• 점심시간이라서 식당에 사람이 많아요.
  = Because it is lunchtime, there are many people in the restaurant.

This is completely natural.

Adding 지금은 just gives a clearer time frame and can make the sentence feel more contextual, like:

• right now, since it’s lunchtime...

So 지금은 is helpful, but not required for the grammar of the rest of the sentence.