How do you know which of the appropriate options (de qui, dont, duquel, etc.) you should use?

- 1) de qui (of/about whom), which can only apply to living things, usually people.
- 2) dont -- Use dont if the subordinate clause needs an object introduced by de/d'. Such clauses may indicate possession or they may contain verbs which are followed by the preposition de. Some of these verbs include 'parler de' (to talk about); 'avoir besoin de' (to need); 'avoir peur de' (to be afraid of); 'tenir de' (to take after).
- 3) duquel -- The contracted forms of de + quel (of/about which): duquel / de laquelle / desquels / desquelles
Note: these forms agree in gender and number with the object they refer to

Note: you can never have de or duquel or dont at the end of the clause like in English.
e.g. you cannot say La fille qui je parle de / La fille laquelle je parle de / La fille je parle dont (The girl I'm speaking of)
Preposition Masculine singular Masculine plural Feminine singular Feminine plural
lequel lesquels laquelle lesquelles
with à auquel auxquels à laquelle auxquelles
with de duquel desquels de laquelle desquelles

Lequel, lesquels, laquelle, lesquelles are pronouns, i.e. they are used in place of a noun. They are used to ask the questions 'which one?' or 'which ones?' They assume the number and gender of the nouns they replace and contract with the prepositions à and de.


Preposition Masculine singular Masculine plural Feminine singular Feminine plural
lequel lesquels laquelle lesquelles
with à auquel auxquels à laquelle auxquelles
with de duquel desquels de laquelle desquelles