Esta semana quiero practicar bastante con mi profesora antes del examen oral.

Because semana is a feminine noun, so the demonstrative this has to agree with it:

• este = masculine singular
• esta = feminine singular

So:

• este libro = this book
• esta semana = this week

Spanish agreement is very important: articles, demonstratives, and many adjectives change to match the noun.

In Spanish, many time expressions can appear without a preposition, especially when they answer when?

So it is normal to say:

• Esta semana = this week
• Hoy = today
• Mañana = tomorrow
• El lunes = on Monday

English often needs a preposition like in or on, but Spanish often does not.

Because Spanish often drops subject pronouns when the verb ending already shows who the subject is.

Here, quiero clearly means I want, so yo is unnecessary.

• quiero = I want
• quieres = you want
• quiere = he/she/it wants

You could say Yo quiero practicar..., but that usually adds emphasis, contrast, or clarity:

• Yo quiero practicar, pero él no.
  = I want to practise, but he doesn’t.

Without emphasis, leaving out yo sounds more natural.

After a conjugated verb like quiero, Spanish normally uses an infinitive for the second verb.

So:

• quiero practicar = I want to practise
• necesito estudiar = I need to study
• prefiero descansar = I prefer to rest

This works like English want to practise, except Spanish does not use a separate word for to here. The infinitive itself does the job.

So practico would be wrong in this structure, because practico is a fully conjugated form meaning I practise.

Here bastante means something like:

• quite a lot
• a fair amount
• rather a lot

So practicar bastante means to practise quite a lot.

It does not always mean exactly the same as mucho:

• mucho = a lot
• bastante = quite a lot / enough / fairly, depending on context

In this sentence, bastante sounds natural and slightly less blunt than mucho. It suggests a good amount of practice, not just a little.

Because bastante is modifying the action, so it works like an adverb here.

• practicar bastante = to practise quite a lot

In Spanish, adverbs like this often come after the verb or after the infinitive.

You could also hear similar patterns like:

• estudiar mucho = to study a lot
• trabajar bastante = to work quite a lot

So the position is normal and natural.

Because the meaning is to practise with my teacher, not to practise my teacher.

• practicar con alguien = to practise with someone
• practicar algo = to practise something

For example:

• Practico español. = I practise Spanish.
• Practico con mi profesora. = I practise with my teacher.

Using a mi profesora would suggest she is a direct object, which does not fit the intended meaning here.

In modern standard Spanish, possessives like mi, tu, su, nuestro usually appear without an article.

So you say:

• mi profesora = my teacher
• mi libro = my book
• nuestra casa = our house

Using la mi profesora is not standard modern Spanish.

Because de + el contracts to del in Spanish.

So:

• de + el = del
• a + el = al

That means:

• antes del examen = before the exam
• voy al colegio = I go to the school

This contraction is normally mandatory.

So antes de el examen oral is not correct in standard Spanish.

Because the expression is antes de.

The preposition de is required after antes when it is followed by a noun:

• antes del examen
• antes de clase
• antes de la cena

So the structure is:

• antes de + noun

Since the noun phrase here starts with el examen oral, de + el becomes del.

In Spanish, descriptive adjectives usually come after the noun.

So:

• examen oral = oral exam
• prueba escrita = written test
• clase difícil = difficult class

English often puts adjectives before the noun, but Spanish usually puts them after.

So oral examen would sound wrong in normal Spanish.

Profesora is the most natural choice in many contexts, especially for:

• a school teacher
• a university teacher
• a private tutor
• someone giving lessons in a subject

Maestra is also possible in some contexts, but it more strongly suggests:

• a primary school teacher
• a traditional schoolteacher sense
• sometimes a special mastery in something

For a sentence like this, especially if the speaker is preparing for an exam and practising with a teacher, mi profesora sounds very natural.

Yes, absolutely. That would also be correct.

The difference is mainly one of nuance:

• practicar bastante = practise quite a lot / a fair amount
• practicar mucho = practise a lot

Both are natural. Bastante can sound a little softer or less absolute than mucho, but in everyday speech the difference is often small.

Not exactly. It is a cognate, but the Spanish pronunciation is different.

In Spain, oral is pronounced roughly like o-RAHL, with:

• a clear Spanish o
• a tapped or trilled r sound, not an English r
• stress on the second syllable: -ral

So even though it looks familiar to an English speaker, it should be pronounced in a Spanish way.