Learn Hardcore Japanese: tosyokan ni ha hon ga ikutu mo arimasu.

図書館に本がいくつもあります。
– Neutral statement.
– Just tells you the fact: At the library, there are many books.
図書館には本がいくつもあります。
– Makes 図書館に the topic or even a contrastive topic.
– Often feels like:
- “In the library (at least), there are many books.”
- “As for the library, there are many books (maybe other places don’t).”

So には often hints at contrast or at least “this is the place we’re talking about now,” while bare に is more purely locational.

Why is it 本が and not 本は?

The pattern here is a very common one:

[Place] には [Thing] があります / います
“At [place], there is/are [thing].”

In this pattern:

[Place]には = topic (what we’re talking about)
[Thing]が = subject (what exists/what there is)

So:

図書館には → “As for the library / In the library”
本が → “books (exist/are there)”
あります → existence verb “there is/are”

If you used 本は, the focus would shift:

図書館には本はいくつもあります。
This sounds like: “In the library, as for books, there are many (maybe magazines are few, but books are many).”
It becomes contrastive: books vs something else.

In the basic “There are X in Y” sentence, Japanese almost always uses が on the thing that exists (本が).

What exactly does いくつも mean here? Is it just “many”?

いくつも does mean “many” here, but its components and nuance are useful to know.

いくつ by itself is a question word:
- いくつありますか。 = “How many are there?”
When you add も after a question word in an affirmative sentence, it often means “a lot / so many”:
- いくつもあります。
  Literally: “There are any amount (of them)” → idiomatically: “There are many (quite a few).”

Nuance of いくつも:

Refers to a relatively large, uncounted number of countable items.
Often carries a feeling like “more than you might think” / “lots of individual items.”

So in context:

本がいくつもあります。
“There are many books” / “There are quite a lot of books.”

What is the difference between いくつも and たくさん?

Both can be translated as “many” / “a lot,” but their feel is a bit different.

たくさん

Very common, neutral “a lot / many / lots of.”
Works with countable and uncountable things.
Example:
- 本がたくさんあります。 = “There are a lot of books.”

いくつも

Literally from the question word いくつ (“how many”) + も.
Emphasizes numerous individual items; often used with things you count as separate pieces.
Feels slightly more subjective, like “quite a number of them,” “many of them.”
Example:
- 本がいくつもあります。 = “There are many books / there are quite a few books.”

You can usually swap them without changing the basic meaning, but:

いくつも is more tied to countability and the idea of multiple separate items.
たくさん is the most neutral, all-purpose “a lot.”

Why is the verb あります and not います?

Japanese has two main “there is / there are” verbs:

ある / あります – for inanimate things (objects, plants, abstract things)
いる / います – for animate things (people, animals)

In this sentence we are talking about books (本), which are inanimate objects, so we use あります:

本がいくつもあります。 = “There are many books.”

If it were people, we’d use います:

図書館には人がたくさんいます。
“There are many people in the library.”

Can we change the word order? For example, can we say 図書館に本がいくつもあります or いくつも本があります?

Yes, Japanese word order is relatively flexible as long as particles stay attached to their words.

Some natural options:

図書館には本がいくつもあります。
(Original) Place-topic → thing → quantity → verb.
図書館に本がいくつもあります。
Same order, but without は; more neutral.
図書館にはいくつも本があります。
Here いくつも comes before 本.
Still means “There are many books in the library,” but puts slightly more emphasis on “many books” as a unit.
本が図書館にいくつもあります。
Grammatically okay; sounds like you’re focusing on “books” first:
“Books — there are many (of them) in the library.”

Main things to remember:

The verb あります comes at the end.
Phrases with particles (図書館に, 本が) can move around before the verb.
いくつも should stay close to the noun or the verb it modifies:
本がいくつもあります or いくつも本があります are both fine.

Why doesn’t 本 have a plural form like “books”? Shouldn’t it be something like 本たち?

Japanese usually does not change the noun form for singular vs plural.

本 can mean “book” or “books” depending on context.
The quantity is shown by:
- context,
- numbers + counters,
- or words like いくつも, たくさん, etc.

In this sentence, いくつも clearly tells us we’re talking about more than one book, so 本 effectively means “books.”

The plural-like suffix 〜たち is:

Mostly used for people and animals (e.g. 子供たち “children,” 友だちたち “friends”).
Only rarely for things, and then usually for a stylistic or emotional effect.

So something like 本たち would sound strange here in normal Japanese.
図書館には本がいくつもあります。 already means “There are many books in the library.”

What exactly is the role of も in いくつも? How is it different from いくつか or just いくつ?

Here’s a useful mini-chart using いくつ:

いくつ？
– Question only → “How many?”
いくつか
– “a few / some (number)”
– Example: 本がいくつかあります。 = “There are a few books / some books.”
いくつも
– “many / quite a few (number)”
– Example: 本がいくつもあります。 = “There are many books.”
いくつでも
– “any number / however many”
– Example: 本はいくつでも借りられます。 = “You can borrow as many books as you like.”

About も specifically:

With question words, X + も often means “all / many / any,” depending on context and whether the verb is positive or negative.
For いくつも:
- いくつもあります → “There are many (of them).”
- いくつもありません → “There aren’t many (of them).”

So in your sentence, いくつも (with positive あります) means “many / quite a few.”

Could we say 図書館では本がいくつもあります instead of 図書館には本がいくつもあります? What’s the difference between に and で here?

With ある／いる (existence verbs), you normally use に, not で, for location:

[Place] に [Thing] があります／います。
= “There is/are [thing] at/in [place].”

So:

✅ 図書館に本があります。
✅ 図書館には本がいくつもあります。
❌ 図書館では本があります。 (unnatural with あります in this meaning)

に marks where something exists or ends up.
で marks where an action takes place.

Examples with で (action):

図書館で本を読みます。 = “I read books at the library.”
図書館では本がよく読まれています。 = “At the library, books are often read.”

In your sentence, あります is just expressing existence, so 図書館には (with に) is correct, not 図書館では.