Grâce à sa bonne mémoire, Paul apprend vite.

In French, the possessive adjective agrees with the thing possessed, not with the owner.

Here, mémoire is a feminine noun, so French uses sa:

• sa mémoire = his memory / her memory

So even though Paul is male, sa is correct because mémoire is feminine.

For comparison:

• son livre = his/her book
• sa mémoire = his/her memory

French does not choose between his and her the way English does in this case. The context tells you whose memory it is.

Because bonne is an adjective, while bien is usually an adverb.

Here, you are describing the noun mémoire, so you need an adjective:

• une bonne mémoire = a good memory

You would use bien to modify a verb, adjective, or another adverb, not a noun:

• Il apprend bien. = He learns well.

So:

• bonne mémoire = correct
• bien mémoire = incorrect

Most French adjectives come after the noun, but some common adjectives often come before it. Bon / bonne is one of them.

So French says:

• une bonne mémoire

not usually:

• une mémoire bonne

This is part of a common pattern with short, frequent adjectives such as beau, bon, grand, petit, jeune, vieux.

Grâce à means something like:

• thanks to
• because of
• due to

It introduces a positive cause or helpful reason.

So:

• Grâce à sa bonne mémoire, Paul apprend vite. = Thanks to his good memory, Paul learns quickly.

A useful contrast:

• grâce à = because of, thanks to, with a positive idea
• à cause de = because of, often with a negative or neutral idea

Examples:

• Grâce à ton aide, j’ai réussi. = Thanks to your help, I succeeded.
• À cause de la pluie, on reste à la maison. = Because of the rain, we’re staying home.

Because grâce à is a fixed expression in French. You learn it as a whole phrase.

So it is:

• grâce à quelqu’un
• grâce à quelque chose

Examples:

• grâce à toi = thanks to you
• grâce à son professeur = thanks to his/her teacher
• grâce à sa bonne mémoire = thanks to his good memory

It is not something you usually analyze word by word as a beginner; it is best memorized as one expression.

In French, a possessive adjective usually replaces the article.

So French says:

• sa bonne mémoire

not:

• la sa bonne mémoire

The same happens with:

• mon livre = my book
• ta voiture = your car
• son ami = his/her friend

So sa already does the job that the or a would otherwise do.

Because the subject is Paul, which is third person singular (he).

The verb is apprendre = to learn

Present tense:

• j’apprends
• tu apprends
• il / elle / on apprend
• nous apprenons
• vous apprenez
• ils / elles apprennent

Since Paul = il, the correct form is:

• Paul apprend

Not exactly.

• apprendre = to learn
• étudier = to study

In this sentence, apprend vite means learns quickly, not studies quickly.

Examples:

• Paul apprend le français. = Paul is learning French.
• Paul étudie le français. = Paul studies French.

Sometimes English uses learn and study in ways that overlap a little, but in French the distinction is often clearer.

Both can mean quickly.

• vite = quickly, fast
• rapidement = quickly, rapidly

Vite is very common and natural in everyday French.
So:

• Paul apprend vite.

sounds simple and natural.

You could also say:

• Paul apprend rapidement.

That is also correct, but it may sound a little more formal or less conversational depending on the context.

French can place a cause or introductory phrase at the beginning of the sentence for emphasis or style, just like English.

So:

• Grâce à sa bonne mémoire, Paul apprend vite.

puts the reason first: Thanks to his good memory...

You could also say:

• Paul apprend vite grâce à sa bonne mémoire.

This is also correct. The meaning is basically the same, but the focus is slightly different.

Beginning with Grâce à sa bonne mémoire highlights the cause first.

The comma is used because Grâce à sa bonne mémoire is an introductory phrase placed before the main clause.

So the sentence is written:

• Grâce à sa bonne mémoire, Paul apprend vite.

This helps readability and is very normal in French.

If the phrase comes later, you usually would not use a comma:

• Paul apprend vite grâce à sa bonne mémoire.

A simple pronunciation guide is:

grâss ah sa bon mem-wahr, Pol ah-pran veet

A bit more carefully:

• Grâce à → sounds like grâss a
• sa → sa
• bonne → bon
• mémoire → roughly may-mwahr
• Paul → Pol
• apprend → ah-pran
• vite → veet

A few important points:

• The final -ce in grâce is not pronounced.
• The final -e in bonne is not pronounced.
• The final -d in apprend is not pronounced.
• The final -e in vite is not pronounced.

No. Mémoire can have several meanings depending on context.

Common meanings include:

• memory
• memoir
• report / dissertation / thesis in some academic contexts

But in this sentence, sa bonne mémoire clearly means his good memory, meaning his ability to remember things well.

Yes. By itself, sa mémoire can mean either:

• his memory
• her memory

French does not distinguish his and her in the possessive adjective here. It depends on context.

In this sentence, we know it means his because the person is Paul.

It is the present tense.

• Paul apprend vite. = Paul learns quickly / Paul is learning quickly

As often happens in French, the present tense can correspond to more than one English form depending on context:

• he learns quickly
• he is learning quickly

In a general statement like this, learns quickly is usually the best translation.