Název knihy je krátký.

Because knihy is in the genitive singular, and Czech uses the genitive after a noun like název when you mean the title of something.

So the structure is:

• název = title/name
• knihy = of the book

This is very common in Czech:

• název knihy = the title of the book
• autor knihy = the author of the book
• obal knihy = the cover of the book

If you used kniha, it would not fit this structure.

Here is the grammatical breakdown:

• Název — nominative singular

  • it is the subject of the sentence
  • masculine inanimate noun

• knihy — genitive singular

  • it depends on název
  • it means of the book

• je — 3rd person singular present of být (to be)

• krátký — nominative singular masculine

  • predicate adjective
  • it agrees with název

So the sentence is built as:

subject + of-phrase + is + adjective

Because krátký agrees with název, not with knihy.

The noun název is:

• masculine
• singular
• nominative
• inanimate

So the adjective must match that, which gives:

• krátký

Compare:

• název je krátký — masculine
• kniha je krátká — feminine
• slovo je krátké — neuter

This kind of adjective agreement is a basic and very important feature of Czech grammar.

The form knihy can be ambiguous, because it can mean different things in different contexts:

• genitive singular of kniha
• nominative plural of kniha
• accusative plural of kniha

But in this sentence, it is clearly genitive singular, because it follows název and forms the phrase název knihy = title of the book.

So even though the form looks like books, the grammar tells you it means of the book here.

It can mean either name or title, depending on context.

For a book, název is normally best understood as title.

Czech usually uses:

• jméno for a person’s name
• název for the name/title of things, works, institutions, places, etc.

So:

• jméno autora = the author’s name
• název knihy = the book’s title

For this sentence, title is the natural choice.

In a normal standard sentence like this, yes, it is necessary.

Czech usually keeps the present tense of být in this kind of sentence:

• Název knihy je krátký.

Leaving out je would sound incomplete or unnatural in ordinary prose and speech.

You may sometimes see omission in:

• notes
• headlines
• very informal fragments

But for a full standard sentence, keep je.

Because Czech does not have articles like English a/an/the.

So Czech often expresses ideas that English would translate with the without adding any extra word.

That means:

• Název knihy je krátký.

can naturally correspond to something like:

• The title of the book is short.

If Czech speakers want to be more specific, they may use a demonstrative such as:

• té knihy = of that/the specific book

For example:

• Název té knihy je krátký.

But very often, no article-like word is needed.

Yes, Czech word order is fairly flexible, but changing it changes the focus or emphasis.

The neutral order here is:

• Název knihy je krátký.

A different order like:

• Krátký je název knihy.

is possible, but it sounds more marked or literary, and it emphasizes krátký.

So for learners, the given sentence is the safest and most natural basic order.

Czech stress is usually on the first syllable of each word.

So the stress pattern is roughly:

• NÁzev
• KNIhy
• je
• KRÁTký

A few pronunciation notes:

• á is a long vowel
• ý is also long
• h in knihy is a real pronounced h, not silent
• ch would be a different sound, but there is no ch here

A rough English-style approximation could be:

• NAA-zev KNI-hi ye KRAAT-kee

That is only approximate, but it helps with the rhythm.

This is a very useful distinction:

• Název knihy je krátký. = a full sentence
• Krátký název knihy = just a noun phrase

So:

• Název knihy je krátký. has a subject and predicate: The book title is short.
• Krátký název knihy means a short book title or the short title of a book, depending on context

In other words, the first one says something complete, while the second one just names a thing.