Les pronoms COD et COI 

COD (Complément d’Objet Direct)

COD (Complément d’Objet Indirect)

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We use the COD pronouns (me, te, le, la, nous, vous and les) when the person or the object comes directly after the verb.

E.g. Il regarde Marie → Il la regarde

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We use the COI pronouns (me, te, lui, nous, vous and leur) when the person or the object comes after a verb and a preposition (e.g. à)

E.g. Il parle à Marie → Il lui parle

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When we use the preposition ‘à’, and then put a place or a thing after it, we use the pronoun ‘y’.

E.g. Elle pense à sa santé → Elle y pense

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When we use the preposition ‘de’, and then put a thing or a certain quantity or of something, we use the pronoun ‘en’.

E.g. Elle mange une pomme → Elle en mange une

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It’s possible to use more than one pronoun in a single sentence.

The order of pronouns is shown above. This is a very important rule to follow as otherwise your sentence will be wrong.