Šířka je správná.

Because šířka is a feminine singular noun, and the adjective správná has to agree with it in gender, number, and case.

Here, the sentence structure is:

• šířka = subject
• je = is
• správná = adjective describing the subject

Since šířka is feminine singular nominative, the adjective also appears in the feminine singular nominative form:

• masculine: správný
• feminine: správná
• neuter: správné

So Šířka je správná uses the correct agreeing form.

It is in the nominative case.

In this sentence, šířka is the subject, and subjects are normally in the nominative in Czech. The adjective správná is also in the nominative because it matches the subject after the verb být.

So both main parts are nominative:

• šířka = nominative singular
• správná = nominative singular feminine

In standard Czech, je is normally required in a sentence like this.

The verb být = to be, and je is the 3rd person singular present form:

• jsem = I am
• jsi / jste = you are
• je = he/she/it is

So:

• Šířka správná is not the normal full sentence in neutral Czech.
• Šířka je správná is the standard form.

In some special contexts, especially headlines, notes, or poetic style, Czech may omit je, but for normal learning and normal speech, keep it.

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

So šířka can mean:

• width
• the width
• sometimes even a width, depending on context

You understand which one is meant from the situation, not from an article.

That is why Šířka je správná can naturally correspond to English with the even though Czech does not say it explicitly.

A rough pronunciation guide is:

• Š sounds like English sh
• long í is a longer ee sound
• ř is the famous Czech sound, something like a rolled/trilled r mixed with a zh/sh quality
• k and a are straightforward

So Šířka sounds roughly like sheerzh-ka, but that is only an approximation.

A few helpful points:

• Czech stress is normally on the first syllable, so ŠÍŘ-ka
• the í is long
• ř is difficult even for learners with good pronunciation, so do not worry if it takes time

Here, správná is an adjective, because it describes the noun šířka.

Compare:

• Šířka je správná. = the width is correct
  
  • správná describes šířka
• Je to uděláno správně. = it is done correctly
  
  • správně is an adverb and describes how something is done

So you need správná, not správně, because the sentence is saying what the width is like, not how something is done.

Yes, Czech word order is flexible, but different orders change the emphasis.

The neutral order is:

• Šířka je správná.

Other orders are possible in context, for example:

• Správná je šířka.
  This can sound contrastive, as if you are saying It is the width that is correct.

Czech often uses word order to show what is already known and what is new or emphasized. But if you are learning the basic pattern, Šířka je správná is the safest and most neutral version.

It can mean both, depending on context.

Common meanings of správný / správná / správné include:

• correct
• right
• proper
• appropriate

In this sentence, a natural English interpretation is something like:

• the width is correct
• the width is right

So správná does not only mean morally right; it can also mean technically correct or suitable.

Usually yes, šířka is the normal noun for width.

It is related to the adjective široký = wide.

A useful family:

• široký = wide
• šířka = width
• délka = length
• výška = height

So this sentence is using the standard noun you would expect for a measurement or dimension.

Yes. That would mean something like That width is correct or The width is correct, depending on context.

Adding ta can make the noun more specific or more pointed:

• Šířka je správná. = neutral, general
• Ta šířka je správná. = that/the width is the correct one

Because Czech has no articles, demonstratives like ten / ta / to are sometimes used when you want extra definiteness or contrast. But they are not required in a neutral sentence.

The dictionary forms are:

• šířka = width
• být = to be
• správný = correct, right

The form je comes from být, and správná is the feminine singular form of správný.

So if you look the words up in a dictionary, you would search for:

• šířka
• být
• správný