kaigi no zyunbi ha hotondo owarimasita.

の links two nouns.

Here, 会議の準備 means the preparations for the meeting or the meeting preparations.

So this の does not only mean possession like John’s book. It can show many kinds of relationships, including:

• possession
• category
• purpose
• association

In this sentence, it shows that the 準備 is connected to the 会議.

は marks the topic of the sentence.

So 会議の準備は means:

• as for the meeting preparations
• regarding the preparations for the meeting

The sentence is talking about the status of those preparations.

A very natural way to understand the structure is:

• 会議の準備は = as for the meeting preparations
• ほとんど終わりました = have mostly/almost finished

So は is not the subject marker here in the English sense. It is setting up what the sentence is about.

Both can be possible in some contexts, but the nuance changes.

• は presents 会議の準備 as the topic:
  As for the meeting preparations, they’re almost finished.
• が would put more focus on the meeting preparations themselves as the thing that has almost finished.

With は, the sentence feels more like a neutral update or report.

With が, it could sound more like:

• emphasizing what has finished
• answering a question like What is almost finished?

So は is very natural if someone is giving a status update.

Here, ほとんど means almost or mostly.

In this sentence, the most natural meaning is:

• almost
• for the most part

So ほとんど終わりました means something like:

• is almost finished
• has mostly been completed

A very important note: ほとんど behaves differently in negative sentences.

• ほとんど終わりました = almost finished / mostly finished
• ほとんど終わっていません = hardly finished at all

So learners should remember that ほとんど can mean different things depending on whether the sentence is affirmative or negative.

This is a very common question.

終わりました is the polite past form of 終わる.

Japanese past tense is often used when something has reached a completed stage by the present moment. In English, we may translate that in different ways depending on what sounds natural:

• finished
• has finished
• is done
• is almost finished

So even though English may prefer is almost finished, Japanese can naturally use 終わりました to report the current situation as something that has progressed to that point.

Here, the idea is that by now, the preparations have progressed so far that they are almost done.

Because 終わる and 終える are different verbs.

• 終わる = to end / to be finished
  intransitive
• 終える = to finish something
  transitive

In this sentence, the focus is on the preparations themselves reaching an almost-finished state:

• 会議の準備はほとんど終わりました。
  The preparations for the meeting are almost finished.

If you wanted to say that someone finished the preparations, you would use a transitive expression such as:

• 会議の準備をほとんど終えました。
  I/we have almost finished the preparations for the meeting.

So the original sentence focuses on the state of the preparations, not on the person doing the action.

Japanese often leaves out the subject or agent if it is clear from context or not important.

This sentence does not say:

• who did the work
• whether it was I, we, the team, etc.

That is normal.

The sentence is mainly giving a status update:

• The preparations for the meeting are almost finished.

If the speaker wanted to specify who did it, they could add that information, but it is often unnecessary in Japanese.

Because ほとんど is an adverb, and adverbs often come before the verb they modify.

Here it modifies 終わりました, telling us the degree of completion:

• ほとんど終わりました = has almost finished

This is very normal Japanese word order.

Japanese nouns usually do not show singular/plural the way English does.

So 準備 can mean:

• preparation
• preparations

In English, the preparations for the meeting sounds more natural here, but the Japanese word itself does not change form.

That is why one Japanese noun can often be translated as either singular or plural depending on context.

Yes, it could be possible, but the nuance is a little different.

• 終わりました sounds like a report that the preparations have reached that stage.
• 終わっています emphasizes the resulting state more directly:
  they are in a finished state

So:

• 会議の準備はほとんど終わりました。
  a natural status update
• 会議の準備はほとんど終わっています。
  also natural, with slightly more emphasis on the current state

In many real situations, both could work.

No. Normally, Japanese is written without spaces.

The standard writing would be:

会議の準備はほとんど終わりました。

Spaces are often added in beginner materials to make the sentence easier to read and to show word boundaries. They are a teaching tool, not normal everyday writing.