Mi profesora corrigió trescientas redacciones este mes.

Mi profesora means my teacher, so it shows possession directly.

Spanish often uses the definite article (la profesora) when possession is obvious from context, but mi profesora is perfectly natural when you want to make it explicit. Compare:

• Mi profesora corrigió trescientas redacciones este mes. = My teacher corrected three hundred essays this month.
• La profesora corrigió trescientas redacciones este mes. = The teacher corrected three hundred essays this month.

So the choice depends on whether you want to say my teacher specifically or just the teacher.

Because profesora is the feminine form, used for a female teacher.

• profesor = male teacher
• profesora = female teacher

Since the sentence says mi profesora, the teacher is female.

Corrigió is the preterite (simple past) form of corregir, for él/ella/usted:

• yo corregí
• tú corregiste
• él/ella/usted corrigió

It matches mi profesora, which is a third-person singular subject (she).

So:

• Mi profesora corrigió... = My teacher corrected...

Because corregir is a stem-changing verb in some forms, and in the preterite third person it becomes corrig-:

• infinitive: corregir
• preterite: corrigió

This is part of a common pattern with -egir / -eguir type verbs:

• dirigir → dirigió
• elegir → eligió
• corregir → corrigió

So corregió is not the correct form here.

Because it agrees with the noun redacciones, which is feminine plural.

In Spanish, the hundreds from 200 to 900 agree in gender with the noun they modify:

• trescientos libros = three hundred books
• trescientas redacciones = three hundred essays/compositions

So:

• redacción is feminine
• plural: redacciones
• therefore: trescientas

Redacción can mean a composition, essay, or piece of writing, especially in a school context.

So trescientas redacciones most naturally means something like:

• three hundred essays
• three hundred compositions
• three hundred written assignments

The best English translation depends on the classroom context.

Because Spanish usually does not use an article in this kind of direct-object phrase when you are talking about a quantity.

So Spanish says:

• corrigió trescientas redacciones

not usually:

• corrigió las trescientas redacciones

The version with las would mean something more specific, like the three hundred essays—a particular known set.

Without las, it just means she corrected three hundred essays.

Because the personal a is mainly used before specific human direct objects.

Here, redacciones are things, not people, so no a is used:

• Corrigió trescientas redacciones. ✅
• Vio a la profesora. ✅ (person)
• Vio el libro. ✅ (thing, so no a)

That is a very normal word order in Spanish. Time expressions like este mes often come at the end of the sentence.

So this structure is natural:

• Mi profesora corrigió trescientas redacciones este mes.

You could also move it for emphasis:

• Este mes, mi profesora corrigió trescientas redacciones.

Both are correct, but the original sentence is the most neutral.

Yes, that is a very good question.

In much of Spain, when the time period is still connected to the present—like hoy, esta semana, este mes, este año—speakers often prefer the present perfect:

• Mi profesora ha corregido trescientas redacciones este mes.

This is especially common if the month is still ongoing.

However, corrigió can still appear depending on region, style, or how the speaker views the action. For example, the speaker may be treating it as a completed event or using a variety of Spanish where the preterite is more common.

So for Spain Spanish, many learners should remember:

• este mes
  • ha corregido = often very typical
• este mes
  • corrigió = possible, but less standard in many Peninsular contexts

The accent mark shows where the stress goes:

• co-rri-GIÓ

Without the accent, the word would not follow the correct written stress pattern.

In Spanish, written accents are important because they show pronunciation and distinguish verb forms. Here, the accent helps mark it as the third-person singular preterite form.

Sometimes, but not always.

• profesora is a general word for female teacher
• maestra often refers more specifically to a primary-school teacher or can carry a slightly different nuance depending on context

If you are talking about a schoolteacher in general, profesora is very safe and common. If the teacher is from a primary-school setting, maestra may also fit.

So in many contexts:

• mi profesora = my teacher

is the most neutral choice.

Because in Spanish, cardinal numbers normally go before the noun they count:

• tres libros
• veinte estudiantes
• trescientas redacciones

This is the standard position, just like in English:

• three hundred essays

So the order is completely normal.

Yes, sometimes you can, but the meaning changes slightly.

• Mi profesora corrigió trescientas redacciones este mes. = My teacher...
• La profesora corrigió trescientas redacciones este mes. = The teacher...

If the conversation already makes it clear whose teacher you mean, Spanish may use la profesora instead of mi profesora. But if you specifically want to say my teacher, keep mi.