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11. He lost the pen which/ that he had given to him.
12. We called the delivery company which/ that Nga often uses.
13. Lan met a girl who/ whom I used to employ.
14. Chi called the lawyer who/ whom my mother knows.
15. He brought a woman who/ whom I worked with last year.
16. We employed the pianist who/ whom Hai introduced.
17. The cake, which I brought, is on the table.
18. An found the book, which belongs to Lan, under the chair.
19. The food, which Huy cooked, was delicious.
20. The bike, which my parents gave me, was stolen.
21. I reported the man, who was arrested, to the police.
22. The teacher, who Ngan asked about her problem, was right.
23. The writer, who my brother dated, was very pretty.
24. The secretary, who Dzung likes, is in the office.
25. We ate the food which/ that I bought.