על הרציף הזה אין הרבה אנשים, ולכן נוכל לשבת עד שהרכבת תגיע.

Hebrew word order is fairly flexible, and putting על הרציף הזה at the beginning gives it extra emphasis.

So:

• על הרציף הזה אין הרבה אנשים = On this platform, there aren’t many people
• a more neutral order would be אין הרבה אנשים על הרציף הזה

Both are grammatical. The version in your sentence highlights the location first, as if the speaker is looking around and commenting specifically on this platform.

In Modern Hebrew, demonstratives like this / that / these normally come after the noun.

So:

• הרציף הזה = this platform
• האישה הזאת = this woman
• הילדים האלה = these children

That is the normal Hebrew pattern. English puts this before the noun, but Hebrew usually puts הזה / הזאת / האלה after it.

When a noun is definite and followed by a demonstrative, Hebrew normally marks both parts as definite.

So Hebrew says:

• הרציף הזה
• literally something like the-platform this

This is just how the language works. You should think of הרציף הזה as one normal unit meaning this platform, not as a word-for-word copy of English structure.

Because על is the normal preposition for being on a platform.

• על הרציף = on the platform

This is similar to English, where we also say on the platform. Hebrew treats the platform as a surface you are standing or sitting on.

Compare:

• בתחנה = at/in the station
• על הרציף = on the platform

So על is the natural choice here.

אין is the standard Hebrew word for there is no / there are no / there isn’t / there aren’t.

So:

• יש אנשים = there are people
• אין אנשים = there are no people
• אין הרבה אנשים = there aren’t many people

A useful way to think about it is that אין is the negative partner of יש.

Also, Hebrew does not need a separate word like English there in this kind of sentence. So Hebrew simply says:

• אין הרבה אנשים not
• there aren’t many people

even though that is how we translate it into English.

Because אין and לא do different jobs.

• אין negates existence/presence
• לא usually negates a verb or whole clause

Examples:

• אין אנשים = there are no people
• לא נשב = we will not sit
• הרכבת לא תגיע בזמן = the train will not arrive on time

In your sentence, the idea is there aren’t many people present, so אין is the correct choice.

Yes, both are possible, but they differ in style.

• הרבה אנשים = many people / a lot of people
  This is the most common and natural everyday phrasing.
• אנשים רבים = many people
  This is more formal, literary, or written.

So in normal speech, אין הרבה אנשים sounds very natural.

Also, הרבה does not change for gender or number here. It simply works as a quantifier meaning many / a lot of.

לכן means therefore, for that reason, or so.

With the added ו־, ולכן means:

• and therefore
• and so
• so

It is a perfectly normal word, though it can sound a bit more formal or written than a very casual אז.

So:

• ולכן נוכל לשבת = and therefore we’ll be able to sit / so we can sit

You can also use לכן without ו־ in other contexts.

Because נוכל adds the idea of ability or possibility.

• נוכל לשבת = we will be able to sit / we can sit
• נשב = we will sit

In this sentence, the logic is:

• there aren’t many people
• therefore, it will be possible for us to sit

So נוכל לשבת fits the meaning better than the more direct נשב.

Because after יכול and its forms, Hebrew normally uses an infinitive.

• אני יכול לשבת = I can sit
• הם יוכלו לבוא = they will be able to come
• נוכל לשבת = we will be able to sit

So this is a standard modal structure:

• נוכל = we will be able
• לשבת = to sit

Together: we will be able to sit

Because after עד ש־ referring to a future event, Hebrew normally uses a future-tense verb.

So:

• עד שהרכבת תגיע = until the train arrives
• עד שהוא יבוא = until he comes
• עד שתיפתח הדלת = until the door opens

This is different from English, which often uses a present tense after until:

• English: until the train arrives
• Hebrew: עד שהרכבת תגיע

So the Hebrew future here is completely normal.

Because the subject is הרכבת, and רכבת is a feminine singular noun.

So the verb has to agree with it:

• הרכבת תגיע = the train will arrive

The verb תגיע comes from להגיע meaning to arrive.

A useful point: the form תגיע can also mean you (masculine singular) will arrive, but in this sentence the subject הרכבת makes it clear that it means she/it will arrive.

Because the sentence is talking about a specific train that both speakers can identify from the situation.

• הרכבת תגיע = the train will arrive

This sounds like the train we are waiting for.

If you changed it, the meaning would become less specific. For example:

• עד שהרכבת תגיע = until the train arrives
• עד שתגיע רכבת = until a train arrives

So the ה־ shows that this is a definite, known train, not just any train.