Esta preposición cambia el significado de la frase.

Because preposición is a feminine noun in Spanish, even though it ends in -ón, which often looks masculine to English speakers.

• esta = feminine singular this
• este = masculine singular this

So:

• esta preposición
• but este significado

The gender has to match the noun, not the English meaning.

In Spanish, the definite article is often used more regularly than in English.

Here, el significado means the meaning, and Spanish normally keeps the article with a noun like this:

• cambia el significado de la frase

English might sometimes say changes the sentence’s meaning or changes meaning, but Spanish naturally uses el significado here.

Also, significado is masculine singular, so the article is el.

Because Spanish usually includes the article when talking about a specific noun, even in general explanatory statements.

So de la frase means of the sentence/phrase.

Compare:

• el significado de la frase = the meaning of the sentence
• el significado de una frase = the meaning of a sentence / one sentence

Using de frase by itself would sound incomplete or unnatural here.

Cambia is the third-person singular present tense of cambiar.

It can mean:

• changes
• is changing, depending on context

Here it means:

• this preposition changes the meaning of the sentence

The subject is esta preposición, which is singular, so the verb is singular too:

• esta preposición cambia
• not cambian

Spanish does not need an auxiliary verb like do/does to make a normal present-tense statement.

English:

• This preposition changes the meaning
• This preposition does change the meaning for emphasis

Spanish simply uses the main verb:

• Esta preposición cambia el significado

If you want emphasis in Spanish, you usually add stress through word order, intonation, or extra words, not an equivalent of does.

Sometimes, yes, but they are not always exactly the same.

• frase = phrase / sentence, depending on context
• oración = sentence or clause, often a bit more grammatical/technical

In many classroom contexts, oración is used for a full grammatical sentence, while frase can be broader.

So:

• el significado de la frase sounds natural and general
• el significado de la oración is also possible, especially in grammar discussions

If you are talking about grammar specifically, oración may sound more precise.

This is the most neutral and standard Spanish word order:

• subject: Esta preposición
• verb: cambia
• object: el significado de la frase

So it follows a pattern similar to English:

• This preposition changes the meaning of the sentence

Spanish can change word order more freely than English, but this version is the most straightforward and natural.

In Spain Spanish, it is pronounced roughly like:

• preh-poh-see-THYON

Key points:

• The stress is on the last syllable: -ción
• In most of Spain, ci sounds like thy in think
• In Latin American Spanish, it would sound more like syon

The written accent mark in preposición shows where the stress goes.

Because Spanish spelling rules require a written accent here to show the correct stress.

Preposición ends in -n, so without an accent, Spanish stress rules would normally place the stress on the second-to-last syllable. But the real stress is on the last syllable:

• pre-po-si-ción

So the accent mark tells you that the stress is irregular.

This pattern is very common with words ending in -ción:

• nación
• información
• preposición

Grammatically, yes, but it is not the most natural choice in everyday Spanish.

• significado is the normal word for meaning
• significación exists, but it sounds more formal, abstract, or linguistic/philosophical

So in most situations, el significado is the best option.

Not by itself in this sentence. Here esta is a demonstrative adjective, so it goes directly before a noun:

• esta preposición = this preposition

If you wanted this one, you would normally use a pronoun:

• Esta cambia el significado = This one changes the meaning

But in your sentence, esta is describing preposición, so it means this.

Not always. English sentence can correspond to different Spanish words depending on context.

Common possibilities:

• frase = phrase / sentence in a broad, everyday sense
• oración = sentence / clause in a grammar sense
• enunciado = utterance / statement, more technical

So frase is fine here, especially in a general explanation, but in a grammar textbook you might also see oración.