Complex relative clauses in French : complete course

Complex Relative Clauses in French: A Complete Guide

1. Simple Definition

A relative clause is a part of a sentence that gives more information about a noun.
In French, complex relative clauses go beyond simple constructions like qui and que.
They use more advanced connectors such as dont, lequel, auquel, and duquel to link ideas with precision.

2. Simple Examples to Get Started

Here are some basic examples to understand what a relative clause looks like:

• C’est l’homme qui parle. → This is the man who is speaking.
  (Simple relative clause using qui)
• C’est le livre que je lis. → This is the book that I am reading.
  (Simple relative clause using que)
• C’est l’ami dont je t’ai parlé. → This is the friend I told you about.
  (More complex: uses dont)
• C’est la table sur laquelle j’ai posé mon café. → This is the table on which I put my coffee.
  (Advanced: uses a preposition + laquelle)

3. Key Elements of Complex Relative Clauses in French

Complex relative clauses use a variety of relative pronouns. Each one has a specific role. Let’s explore them.

3.1 Using Dont

Dont replaces a noun introduced by the preposition de. It is used when the verb or expression requires de.

• Je te parle d’un projet. → C’est le projet dont je te parle.
  This is the project I am talking to you about.
• J’ai besoin d’un stylo. → C’est le stylo dont j’ai besoin.
  This is the pen I need.
• Elle est fière de ses enfants. → Ce sont les enfants dont elle est fière.
  These are the children she is proud of.

3.2 Using Lequel, Laquelle, Lesquels, Lesquelles

Lequel (and its forms) is used after a preposition other than de. It agrees in gender and number with the noun it refers to.

Gender / Number	Form	Example
Masculine singular	lequel	Le stylo avec lequel j’écris. — The pen with which I write.
Feminine singular	laquelle	La chaise sur laquelle tu es assis. — The chair on which you are sitting.
Masculine plural	lesquels	Les outils avec lesquels il travaille. — The tools with which he works.
Feminine plural	lesquelles	Les raisons pour lesquelles elle est partie. — The reasons for which she left.

3.3 Contractions: Auquel and Duquel

When lequel combines with the prepositions à or de, contractions are formed.
Auquel comes from à + lequel. Duquel comes from de + lequel.

Preposition	Masculine singular	Feminine singular	Masculine plural	Feminine plural
à +	auquel	à laquelle	auxquels	auxquelles
de +	duquel	de laquelle	desquels	desquelles

• C’est le cours auquel je participe. → This is the course in which I am participating.
  (participer à → auquel)
• C’est le bâtiment à côté duquel il habite. → This is the building next to which he lives.
• Ce sont les problèmes auxquels nous devons faire face. → These are the problems we must face.

3.4 Using Où for Place and Time

Où is used as a relative pronoun to refer to a place or a moment in time. It is simpler but still important in advanced structures.

• C’est la ville où je suis né. → This is the city where I was born.
• Je me souviens du jour où nous nous sommes rencontrés. → I remember the day when we met.

4. Why Complex Relative Clauses in French Are Important

Understanding complex relative clauses helps you go from sounding basic to sounding fluent and natural in French.
Here is why they matter:

• They let you combine sentences smoothly instead of using many short, choppy sentences.
• They add precision — you can describe things in detail without repeating the noun.
• They are common in written French — newspapers, books, and formal emails use them constantly.
• They are tested in official exams such as DELF B1, B2, and DALF C1.
• They help you understand native speakers — French speakers use these structures in everyday speech.

5. Comparison with Other Languages

Let’s see how French relative clauses compare to Spanish and English equivalents.

Feature	French	Spanish	English
Basic subject pronoun	qui	que	who / that
Basic object pronoun	que	que	that / which (often omitted)
Replacing de + noun	dont	cuyo/a (possessive) or del que	whose / of which
After a preposition	lequel / laquelle etc.	el cual / la cual etc.	which / whom
Gender agreement	Yes — required	Yes — required	No — not required
Preposition position	Before the relative pronoun	Before the relative pronoun	Often moved to end of sentence

Key observation: In English, it is common to say “The table I put my coffee on.” In French and Spanish, you cannot end a sentence with a preposition. You must say: “La table sur laquelle j’ai posé mon café.”

6. Full Example

Let’s build a rich paragraph in French using several complex relative clauses. Each one is explained below.

Marie travaille dans une entreprise dont le directeur est très connu.
C’est une société à laquelle elle s’est beaucoup investie.
Les collègues avec lesquels elle travaille sont très compétents.
Elle se souvient du jour où elle a signé son contrat.
C’est un emploi auquel elle tient beaucoup.

Translation and explanations:

• dont le directeur est très connu → whose director is very well-known. (dont replaces de cette entreprise)
• à laquelle elle s’est beaucoup investie → in which she has invested a lot. (s’investir dans → à laquelle)

les collègues avec lesquels elle travaille → the colleagues with whom she works. (avec + lesquels after a preposition)

le jour où elle a signé son contrat → the day when she signed her contract. (où for time reference)

un emploi auquel elle tient beaucoup → a job she cares deeply about. (tenir à → auquel)

8. Key Takeaways

Here is a clear summary of everything you need to remember about complex relative clauses in French.

Relative Pronoun	When to Use It	Quick Example
dont	Replaces de + noun (verb or expression requires de)	Le projet dont je te parle.
lequel / laquelle	After a preposition (other than de); agrees in gender and number	La chaise sur laquelle tu es assis.
auquel / auxquels	Contraction of à + lequel/lesquels; verb requires à	Le cours auquel je participe.
duquel / desquels	Contraction of de + lequel/lesquels; used with compound prepositions	Le bâtiment à côté duquel il habite.
où	Refers to a place or a point in time	Le jour où nous nous sommes rencontrés.

Three Rules to Always Keep in Mind

• Rule 1 — Gender and number agreement: Lequel and its forms always agree with the noun they replace. Never use a masculine form when referring to a feminine noun.
• Rule 2 — Preposition placement: In French, the preposition always comes before the relative pronoun. You cannot move it to the end of the sentence as you can in English.
• Rule 3 — Choose dont vs. duquel carefully: Use dont when the verb or adjective directly requires de. Use duquel / de laquelle etc. when the preposition is part of a longer compound expression such as à côté de, en face de, or près de.

Common Mistakes to Avoid

• Mistake: C’est le projet que je te parle.
  Correction: C’est le projet dont je te parle.
  Parler de requires dont, not que.
• Mistake: Les raisons pour que elle est partie.
  Correction: Les raisons pour lesquelles elle est partie.
  After a preposition, use lequel / laquelle, not que.
• Mistake: C’est le problème auquel nous parlons.
  Correction: C’est le problème dont nous parlons.
  Parler de → dont. Use auquel only when the verb requires à.
• Mistake: Le bâtiment à côté dont il habite.
  Correction: Le bâtiment à côté duquel il habite.
  Compound prepositions ending in de require duquel / de laquelle, not dont.

A Simple Decision Guide

When you need to choose the right relative pronoun, ask yourself these questions in order:

1. Does the verb or adjective require de? → Use dont.
2. Is there a compound preposition ending in de (e.g., à côté de, en face de)? → Use duquel / de laquelle / desquels / desquelles.
3. Does the verb require à? → Use auquel / à laquelle / auxquels / auxquelles.
4. Is there another preposition (e.g., avec, sur, pour, sans)? → Use lequel / laquelle / lesquels / lesquelles preceded by that preposition.
5. Does the antecedent refer to a place or time? → Use où.

9. Sources

• Riegel, M., Pellat, J.-C., & Rioul, R. (2018). Grammaire méthodique du français (6th ed.). Presses Universitaires de France. — A comprehensive and authoritative reference grammar of the French language, widely used in university linguistics programs.
• Grevisse, M., & Goosse, A. (2016). Le Bon Usage: Grammaire française (16th ed.). De Boeck Supérieur. — The most detailed descriptive grammar of French, considered the standard reference for advanced grammar questions including relative pronouns and their uses.
• Council of Europe. (2020). Common European Framework of Reference for Languages: Learning, Teaching, Assessment — Companion Volume. Council of Europe Publishing. — The official CEFR framework document defining language competence levels, including the grammatical accuracy expectations at C1 level relevant to complex syntactic structures.