jeoneun balpyohal ttaemada ginjangdwaeyo.

A natural breakdown is:

• 저는 = as for me / I
• 발표할 = to present / giving a presentation in a form that modifies the next noun
• 때마다 = every time / whenever
• 긴장돼요 = get nervous / feel nervous

So the structure is basically:

As for me, whenever I present, I get nervous.

는 is the topic marker, while 가 is the subject marker.

Here, 저는 sounds natural because the speaker is making a general statement about themself:
As for me, I get nervous whenever I present.

If you said 제가 발표할 때마다 긴장돼요, it would put a bit more focus on I. That can sound like:

• I’m the one who gets nervous every time I present
• or it can feel slightly more emphatic

Both are possible, but 저는 is very natural for a general personal statement.

Yes. Korean often drops subjects and topics when they are clear from context.

So 발표할 때마다 긴장돼요 is also completely natural and often sounds more conversational.

You include 저는 when you want to:

• make the topic clear
• add a little contrast
• or sound slightly more complete

The base verb is 발표하다, which means to present, to give a presentation, or sometimes to announce, depending on context.

Here:

• 발표 = presentation / announcement
• 하다 = to do
• 발표하다 = to do a presentation, to present

Then 하다 changes to 할 because it is being used before 때.

So:

• 발표하다 = to present
• 발표할 때 = when presenting / when I present

Because 때 is a noun meaning time or the time when. In Korean, verbs often change into a modifier form before nouns.

So:

• 발표하다 = to present
• 발표할 때 = the time when one presents / when presenting

This -ㄹ/을 form is very common before 때 when talking about when something happens.

So 발표할 때마다 literally feels like:

at each time that I present

때마다 means every time or whenever.

It is made of:

• 때 = time
• 마다 = every / each

So:

• 갈 때마다 = every time I go
• 볼 때마다 = every time I see it
• 발표할 때마다 = every time I present

This shows a repeated situation, not just one single event.

The base form is 긴장되다.

• 긴장 = tension / nervousness
• 되다 = to become

So 긴장되다 literally has the idea of to become tense/nervous.

In everyday Korean, 긴장돼요 is a very common way to say:

• I get nervous
• I feel nervous

You may also see 긴장해요 from 긴장하다. Both are used, but 긴장돼요 often feels a little more like nervousness happens to me or I become nervous, while 긴장해요 can sound a bit more direct: I am nervous / I tense up.

Yes, 긴장돼요 is in the polite present tense.

But with 때마다, the meaning becomes habitual:

• not I am nervous right now
• but I get nervous whenever this happens

So the present tense here is being used for a repeated pattern, which is why English often translates it as:

• I get nervous every time I present
• I feel nervous whenever I present

Because the correct contraction of 되어요 is 돼요.

So:

• 되다
• 되어요
• 돼요

This is a very common spelling point in Korean.
So 긴장돼요 is correct, and 긴장되요 is not standard.

It uses the -요 ending, so it is polite informal speech.

That means it is appropriate in many everyday situations:

• talking to someone you do not know well
• speaking politely in class or at work
• general conversation

Related versions:

• 발표할 때마다 긴장돼. = casual
• 저는 발표할 때마다 긴장됩니다. = more formal

Usually 발표 suggests a presentation, especially in school, work, or a meeting.

So this sentence most naturally means something like:

• giving a class presentation
• presenting in front of people
• making a formal presentation

Depending on context, 발표하다 can also mean to announce, but in this sentence learners will usually understand it as give a presentation.

Yes. Korean usually puts the time/background information first and the main feeling or action at the end.

So Korean says, in effect:

• As for me
• every time I present
• I get nervous

The main verb or predicate, 긴장돼요, comes at the end, which is normal in Korean.