Ce livre parle de l'enfance de Marie.

In French, the verb parler needs a preposition to introduce the topic you are talking about, and that preposition is usually de.

• parler de quelque chose = to talk/speak about something
  
  • Ce livre parle de l’enfance de Marie. = This book is about Marie’s childhood.
  • Nous parlons de politique. = We are talking about politics.

Parler sur exists but is rare and quite marked; it can mean something like “to speak about/against someone” in a critical way (e.g. Il parle sur elle = he bad-mouths her). For neutral “be about / talk about”, you want parler de.

You also can’t drop the de the way English can drop “about” in some contexts. So Ce livre parle Marie is incorrect; you must say parle de Marie or parle de l’enfance de Marie.

Both ce and cet mean “this/that” (masculine singular), but their use depends on pronunciation:

• ce is used before a masculine noun starting with a consonant sound:

  • ce livre (livre starts with the consonant sound /l/)
  • ce garçon

• cet is used before a masculine noun starting with a vowel sound or mute h:

  • cet arbre, cet homme, cet hôpital

Since livre begins with the consonant sound l, you must say ce livre, not cet livre.

The de is the preposition that links the verb parle to its topic.

• parler de X = to talk/be about X

In this sentence you have a chain of de:

• parle de l’enfance = is about (the) childhood
• l’enfance de Marie = the childhood of Marie

So structurally it’s:

• Ce livre parle de [l’enfance de Marie].
  → parle de = is about
  → [l’enfance de Marie] = noun phrase: Marie’s childhood

Both de’s are needed:

• one to connect parle with its object (parle de l’enfance)
• one to show possession (l’enfance de Marie = Marie’s childhood).

This is a case of elision in French.

• The normal feminine singular article is la (the).
• When la is followed by a word starting with a vowel sound or mute h, it becomes l’ and drops the a:
  • la enfance → l’enfance
  • la amie → l’amie

The same happens after de:

• de + la enfance → de l’enfance
• de + la amie → de l’amie

So de l’enfance is just de la enfance with mandatory elision for smoother pronunciation.

French uses articles much more systematically than English, especially with abstract nouns like enfance, vie, liberté, amour.

• l’enfance de Marie literally = the childhood of Marie
• But natural English chooses a possessive: Marie’s childhood

In French it would sound odd to drop the article and say ∗enfance de Marie. You almost always need an article (or another determiner):

• l’enfance de Marie (the childhood of Marie)
• son enfance (her childhood)
• une enfance heureuse (a happy childhood)

So l’ here is just the normal definite article that French requires where English can omit the.

Both are grammatically correct and mean almost the same thing:

• Ce livre parle de l’enfance de Marie.
  → more explicit: “about the childhood of Marie.”

• Ce livre parle de son enfance.
  → “about her childhood.”

Differences:

1. Clarity of who “son” refers to

   • son enfance could mean “his childhood” or “her childhood” (son is used before a feminine noun beginning with a vowel for sound reasons).
   • In isolation, son enfance is ambiguous in gender. Context must clarify.
   • l’enfance de Marie is fully explicit: it’s Marie’s childhood.

2. Style

   • l’enfance de Marie sounds slightly more formal or emphatic, because it names the person.
   • son enfance is shorter and more natural when Marie is already clearly the subject of discussion.

If you’ve just mentioned Marie and it’s obvious you’re talking about her, Ce livre parle de son enfance is very natural. If you’re introducing her or want to emphasise the name, de l’enfance de Marie is better.

There are two rules here:

1. Elision with la → l’

   • la becomes l’ before a vowel sound:
     
     • la enfance → l’enfance
       So la enfance is ungrammatical; it must be l’enfance.

2. Normal French word order for “X of Y”

   • French generally uses [noun] + de + [possessor]:
     
     • l’enfance de Marie
     • le livre de Paul
   • Putting the possessor first (de Marie l’enfance) is not standard modern French; it sounds archaic or poetic at best.

So the regular, modern form is l’enfance de Marie:
[article + noun] + de + [name].

Parle is third person singular, present tense of parler:

• je parle
• tu parles
• il/elle/on parle
• nous parlons
• vous parlez
• ils/elles parlent

This is the “historical” or “narrative” present, used in both English and French to talk about the content of books, films, and works of art:

• Ce livre parle de… = This book is about…
• Ce film raconte l’histoire de… = This film tells the story of…

Even if the book was written long ago and isn’t changing, the present tense is used because the content is considered “always true” every time you read or describe the book.

• livre is masculine. You can see this because the demonstrative is ce (masculine), not cette (feminine):

  • ce livre (this book)
  • cette table (this table – feminine)

• enfance is feminine. You see this from the article l’, which replaces la (feminine):

  • l’enfance = la enfance with elision
  • Compare: l’homme = le homme with elision (masculine), but you only know that from dictionary / other forms; for enfance, dictionaries mark it as feminine: une enfance, son enfance heureuse (not son enfance heureux).

So in this sentence:

• Ce → masculine, signals livre is masculine.
• l’ before enfance, and known vocabulary, indicate enfance is feminine.

A few points:

• de l’enfance:

  • de is pronounced /də/ (often very short, almost like “duh”).
  • l’enfance is /lɑ̃.fɑ̃s/. The en and an are nasal vowels: no clear “n” sound at the end.
  • Together: /də lɑ̃.fɑ̃s/ — smooth link between de and l’enfance.

• de Marie:

  • de again /də/.
  • Marie is /ma.ʁi/ (with a French r, not an English “ree”).

No liaison is required between parle and de (you don’t say parl-de); they stay separate. The main thing is the elision l’enfance and the nasal vowels in enfance.