A professora escreve a letra da canção no quadro.

In Portuguese, common nouns usually take an article in normal sentences. So a professora means the teacher.

English often omits the article where Portuguese does not. Compare:

• Ela é professora. = She is a teacher.
• A professora escreve... = The teacher writes...

So in this sentence, the article is the normal choice.

Yes. Professora is feminine, so it refers to a female teacher.

The masculine form is professor:

• a professora = the female teacher
• o professor = the male teacher

Portuguese often marks gender clearly in nouns like this.

Escreve is the he/she/it form of escrever in the present tense.

In Portuguese, the simple present can describe:

• a habitual action
• a general fact
• sometimes what is happening now, depending on context

So A professora escreve... can mean something like The teacher writes... or, in context, The teacher is writing...

In European Portuguese, if you want to make the ongoing action very explicit, you often use:

• A professora está a escrever...

That is the usual progressive form in Portugal.

Letra can mean several things, including:

• a letter of the alphabet
• handwriting
• song lyrics

Here, because of da canção, it means the lyrics or the words of the song.

A very important point for English speakers: Portuguese often uses singular letra where English uses plural lyrics.

So:

• a letra da canção = the song lyrics

Da is a contraction of de + a.

• de = of / from
• a = the

So:

• da canção = of the song

This happens very often in Portuguese:

• do = de + o
• da = de + a
• dos = de + os
• das = de + as

Canção means song, especially as a piece with words/lyrics.

Música can mean:

• music in general
• a song, in many everyday contexts

But here canção is especially suitable because the sentence talks about the lyrics. So a letra da canção is a precise and natural combination.

In Portugal, canção can also sound a bit more careful or literary than música, depending on context.

No is a contraction of em + o:

• em = in / on
• o = the

So no quadro literally looks like in the board, but in natural English it is usually on the board.

In a classroom context in Portugal, quadro usually means the classroom board:

• blackboard
• chalkboard
• whiteboard

The exact type depends on the situation.

Because Portuguese normally uses em with places where something is written or displayed.

So you say:

• no quadro = on the board
• na parede = on the wall
• no papel = on the paper

Sobre usually means on top of or about. It is not the normal choice for writing surfaces in this kind of sentence.

So:

• O livro está sobre a mesa. = The book is on the table.
• A professora escreve no quadro. = The teacher writes on the board.

Yes, Portuguese word order is somewhat flexible, but the original sentence is the most neutral and natural.

Original:

• A professora escreve a letra da canção no quadro.

You could also say:

• A professora escreve no quadro a letra da canção.

That is still correct, but it shifts the rhythm and focus a little.

If you put no quadro first:

• No quadro, a professora escreve a letra da canção.

that gives extra emphasis to the location.

So the original version is a good standard pattern: subject + verb + object + place

The ç is called a cedilla. It makes the c sound like s before a, o, or u.

So:

• ca would normally sound like ka
• ça sounds like sa

That is why canção has an s sound in the middle.

Also, the ending -ão is a very common nasal ending in Portuguese. English does not really have the same sound, so it takes practice.

The stress is on the last syllable:

• can-ÇÃO

A rough English-friendly approximation is kan-SOWN, but that is only approximate, especially in European Portuguese, where the vowels are reduced more.