Al principio, me daba miedo hablar en voz alta, pero ahora me siento más tranquilo.

Al principio means at first or in the beginning of a situation.

In this sentence, it means that in the early stage, the speaker was afraid to speak out loud.

En principio is different. It usually means in principle or theoretically.

• Al principio, me daba miedo... = At first, I was afraid...
• En principio, debería funcionar. = In principle, it should work.

So for time or an initial stage, use al principio.

Both are possible, but they focus on the idea differently.

• Me daba miedo hablar en voz alta = Speaking out loud scared me / gave me fear
• Tenía miedo de hablar en voz alta = I was afraid to speak out loud

With dar miedo, the thing itself is presented as the cause of the fear.
With tener miedo, the emphasis is more on the person’s emotional state.

So in this sentence, hablar en voz alta is treated as the thing that caused fear.

Daba is the imperfect tense, which is often used for:

• ongoing states in the past
• repeated feelings or habits
• background description

Here, the idea is that at the beginning, the speaker used to feel that fear, or that fear was an ongoing state.

• Me daba miedo hablar en voz alta = I was afraid / it used to scare me
• Me dio miedo hablar en voz alta = It scared me at one specific moment

So daba fits better because this was not just one sudden event.

In me daba miedo, me means to me.

Literally, dar miedo works like this:

• Algo me da miedo = Something gives fear to me

So:

• Hablar en voz alta me daba miedo = Speaking out loud scared me

This is a very common Spanish structure:

• Me da vergüenza = It embarrasses me
• Me da pereza = It makes me feel lazy / I can’t be bothered
• Me da igual = It’s all the same to me

So me is not reflexive here; it is the person affected by the feeling.

Because in Spanish, an infinitive can act a bit like a noun in English.

Here, hablar en voz alta means speaking out loud.

So the structure is basically:

• Hablar en voz alta me daba miedo = Speaking out loud scared me

Spanish often uses the infinitive this way:

• Fumar es malo. = Smoking is bad.
• Viajar es divertido. = Travelling is fun.

So hablar is not tied to a specific subject here; it refers to the action in general.

En voz alta is a fixed expression meaning out loud or aloud.

• leer en voz alta = to read out loud
• hablar en voz alta = to speak out loud

This is slightly different from hablar alto.

• hablar en voz alta = speak aloud, not silently or under your breath
• hablar alto = speak loudly, with a high volume

So in this sentence, en voz alta is the most natural way to say out loud.

Both can work, but me siento focuses more on the speaker’s inner feeling.

• Me siento más tranquilo = I feel calmer / more at ease
• Estoy más tranquilo = I am calmer

In many situations, the difference is small. But sentirse is especially common when talking about emotions, physical condition, or personal sensations.

So me siento más tranquilo sounds very natural because the speaker is describing how they feel internally now.

Because the adjective has to agree with the person who is speaking.

• A male speaker would say tranquilo
• A female speaker would say tranquila

So:

• me siento más tranquilo = said by a man
• me siento más tranquila = said by a woman

The adjective matches the speaker, not the noun voz or anything else in the sentence.

Más means more, so it creates a comparison with the earlier situation.

The sentence contrasts:

• before: the speaker was afraid
• now: the speaker feels more calm than before

Without más, the meaning would still make sense:

• Ahora me siento tranquilo = Now I feel calm

But más tranquilo highlights the change over time more clearly.

Yes, absolutely. That would also be natural.

• Me daba miedo hablar en voz alta
• Tenía miedo de hablar en voz alta

Both mean something very close to I was afraid to speak out loud.

The difference is mainly in structure and emphasis:

• me daba miedo focuses on the action as the source of fear
• tenía miedo de focuses on the person having fear

Both are common, and both are good Spanish.

It is acceptable and natural, but with a short introductory phrase like Al principio, some writers would leave it out.

So both are possible:

• Al principio, me daba miedo hablar en voz alta...
• Al principio me daba miedo hablar en voz alta...

The comma helps mark a pause and makes the sentence a little clearer, but it is not absolutely required in every case.