To complete the sentences using relative pronouns, you can follow these steps:
1- Nous recherchons des arbustes **qui** ne craignent pas le gel.
Explanation: The relative pronoun "qui" is used to refer to the arbustes and introduce the subordinate clause describing a characteristic of the bushes.
2- Je peux te prêter un vélo... **dont** je ne me sers pas.
Explanation: The relative pronoun "dont" is used to show possession or relationship. In this case, it connects the bike (vélo) to the fact that the speaker does not use it.
3- Le banc sur **lequel** tu es assis vient d'être repeint.
Explanation: The relative pronoun "lequel" is used to refer to the bench (banc) and specify the location where the person is sitting. It agrees in gender and number with the noun it refers to.