Ya he dejado escrita la dedicatoria en la tarjeta, pero todavía no sé si suena demasiado seria.

Both are possible, but they are not exactly the same.

• He escrito la dedicatoria = I have written the dedication/message.
• He dejado escrita la dedicatoria = literally something like I have left the dedication written.

This dejar + participle/adjective structure often emphasizes the resulting state. It suggests that the task is already done and now the message is there, written on the card.

So he dejado escrita sounds a bit more like:

• I’ve already got the dedication written
• I’ve already written the dedication down

It highlights the completed result, not just the action of writing.

In this sentence, dejar escrita means to leave something written or to get something into a written state.

This pattern is common in Spanish:

• dejar hecha la comida = to leave the meal made / to have the meal prepared
• dejar cerrada la puerta = to leave the door closed
• dejar preparada la maleta = to leave the suitcase ready

So:

• he dejado escrita la dedicatoria = I’ve left the dedication written / I’ve already written the dedication

It often implies:

1. the action is finished, and
2. the result remains.

Because escrita agrees with la dedicatoria, which is feminine singular.

• la dedicatoria → feminine singular
• therefore → escrita

Compare:

• He dejado escrito el mensaje
• He dejado escrita la carta
• He dejado escritos los nombres
• He dejado escritas las instrucciones

This agreement is very common in structures like dejar + participle.

Ya usually means already in this kind of sentence.

So:

• He dejado escrita la dedicatoria = I have written the dedication
• Ya he dejado escrita la dedicatoria = I have already written the dedication

It adds the idea that this part is completed, often with a contrast coming next. And that is exactly what happens here:

• Ya he dejado escrita la dedicatoria..., pero todavía no sé...
• I’ve already written the dedication..., but I still don’t know...

So ya helps set up the contrast with todavía.

They are opposites in this sentence.

• ya = already
• todavía = still / yet

So the sentence creates a nice contrast:

• Ya he dejado escrita la dedicatoria = that part is already done
• pero todavía no sé = but I still don’t know

This is very natural Spanish.

You could think of it as:

• The writing is done already, but the doubt remains.

Yes. In this sentence, todavía and aún are basically interchangeable:

• ...pero todavía no sé...
• ...pero aún no sé...

Both mean ...but I still don’t know...

In everyday Spanish, todavía is often felt as slightly more common and neutral in conversation, but aún is also very normal.

This is the present perfect: he dejado.

In Spain, the present perfect is very commonly used for actions connected to the present, especially when the result matters now.

Here, the speaker means:

• the dedication has been written,
• and that matters at this moment because they are now wondering if it sounds too serious.

So in Spain, ya he dejado escrita... sounds very natural.

In many parts of Latin America, people might more often say:

• Ya dejé escrita la dedicatoria...

But in Spain, he dejado is especially common in this kind of context.

Here la dedicatoria means the short message written in a card, book, or gift for someone.

It is not the same as English dedication in every context. In Spanish:

• dedicatoria = a written dedicatory message
• dedicación = dedication in the sense of commitment, effort, devotion

So in this sentence, dedicatoria is the personal message written on the card.

Because the message is physically written on/in the card.

• en la tarjeta = on the card / in the card

This is the natural preposition for location here.

Other options would change the meaning:

• de la tarjeta = of the card / from the card
• para la tarjeta = for the card

So if you want to say where the dedication appears, en la tarjeta is the normal choice.

Because suena means sounds, and that is exactly the idea here: the speaker is judging the impression the wording gives.

• suena demasiado seria = it sounds too serious
• es demasiado seria = it is too serious

Using suena makes the statement softer and more subjective. The speaker is not saying the message definitely is too serious; they are saying they are unsure how it comes across.

This is very common when talking about language:

• Suena raro = It sounds strange
• Suena natural = It sounds natural
• Suena demasiado formal = It sounds too formal

Here si means whether.

• No sé si suena demasiado seria = I don’t know whether it sounds too serious

In English, if is also possible in many cases:

• I don’t know if it sounds too serious

So the Spanish si after no sé often corresponds to English if/whether.

Just remember this is si without an accent.

• si = if / whether
• sí = yes

No accent mark is needed here.

The adjective is:

• serio = serious
• seria = serious (feminine)

It is feminine because it refers to the thing that suena, understood as the dedicatoria or the wording of the message.

So:

• la dedicatoria → feminine
• demasiado seria → feminine

And no written accent is needed on seria.

Be careful not to confuse:

• seria = serious / or I would be depending on context
• sería = would be

Here it is clearly the adjective seria.

The subject is understood from the context. It is the dedicatoria or the text of the message.

So the idea is:

• no sé si la dedicatoria suena demasiado seria
• I don’t know if the dedication/message sounds too serious

Spanish often leaves out repeated nouns when they are obvious from context.

Yes, that is possible if the context already makes clear what la refers to:

• Ya la he dejado escrita en la tarjeta...

That would mean:

• I’ve already written it on the card...

But if you want to introduce the noun clearly, la dedicatoria is better.

So:

• Ya he dejado escrita la dedicatoria... = clearer, more explicit
• Ya la he dejado escrita... = more compact, used when the listener already knows what you mean

Yes, but it is natural Spanish word order.

The pattern is:

• he dejado + escrita + la dedicatoria

The participle/adjective escrita is placed before the noun it describes because it is part of the structure dejar + participle + object.

This is different from simply describing the noun in a normal noun phrase. Here, escrita is linked to the action of dejar.

So the sentence is not just saying the written dedication. It is saying:

• I have left the dedication written

That is why the order feels a little different from what an English speaker might expect.

Yes, too serious is the direct meaning, and it works well here.

But in context, it often carries the nuance of:

• too formal
• too solemn
• too stiff
• too heavy in tone

When talking about a message in a card, demasiado seria usually means the wording may feel less warm, playful, or natural than the speaker wants.

So seria here is about tone, not just personality.