La regla és clara.

Because regla is a feminine noun in Catalan, so it takes the feminine singular article la.

• la regla = the rule
• el llibre = the book

In Catalan, as in many Romance languages, nouns have grammatical gender, and the article must match that gender.

One clue is the ending: nouns ending in -a are often feminine in Catalan, and regla is one of them.

That said, you cannot rely on the ending 100% of the time, so it is best to learn nouns together with their article:

• la regla
• la casa
• la taula

Learning the article and noun together helps you remember gender naturally.

És is the 3rd person singular form of the verb ser, meaning is.

So:

• jo soc = I am
• tu ets = you are
• ell/ella és = he/she is

In La regla és clara, és links the subject (la regla) with the adjective (clara), just like is in English.

The accent in és is part of the correct spelling and also helps distinguish it from other forms such as es.

• és = is
• es = a pronoun, often meaning something like oneself / each other / to oneself depending on context

So the accent is important because it changes the word.

Because adjectives in Catalan usually agree in gender and number with the noun they describe.

Since regla is:

• feminine
• singular

the adjective must also be:

• feminine
• singular

So:

• clar = masculine singular
• clara = feminine singular
• clars = masculine plural
• clares = feminine plural

That is why La regla és clara is correct.

Not always, but in sentences like this it commonly comes after the verb, because it is a predicate adjective.

Structure here:

• La regla = subject
• és = verb
• clara = adjective describing the subject

This is similar to English: The rule is clear.

When an adjective is directly attached to a noun inside a noun phrase, it often comes after the noun in Catalan as well:

• una regla clara = a clear rule

Some adjectives can come before the noun, but that depends on the adjective and style.

Because Catalan usually does not use a dummy subject like English it in this kind of sentence.

English says:

• It is clear
• The rule is clear

But Catalan normally uses the actual subject directly:

• La regla és clara

Catalan does not need an extra placeholder subject.

Yes, in some contexts La regla està clara is possible, but it is not exactly the same nuance.

• La regla és clara = the rule is clear by nature / in general / objectively
• La regla està clara = the rule is clear now / has become clear / is understood in the situation

This relates to the common Catalan distinction between ser and estar. In many beginner contexts, ser is the safer and more neutral choice for a statement like this.

A simple pronunciation guide is:

lah RREH-gluh es KLAH-ruh

A few notes:

• la is short and simple
• regla has a rolled or tapped r
• és sounds roughly like ess
• clara begins with a clear cl cluster
• the stress is on re in regla and on cla in clara

Exact pronunciation varies a bit by dialect.

The normal, neutral order is:

La regla és clara.

That is:

1. subject
2. verb
3. adjective

Catalan does allow other word orders for emphasis or style, but this is the most standard and natural order for a basic statement.

Normally, no. In this sentence, la is needed because you are talking about the rule, not just rule in general.

Compare:

• La regla és clara. = The rule is clear.
• Una regla és clara. = A rule is clear.

Catalan generally requires an article where English sometimes does too, and in this sentence the definite article is an essential part of the noun phrase.

The plural would be:

Les regles són clares.

Changes:

• la → les
• regla → regles
• és → són
• clara → clares

Everything changes to match the plural subject.