1. The two young men with whom you are acquainted are not good persons. 
2. My father whom you met this morning goes swimming everyday. 
3. Mary and Margaret whom you met yesterday are twins. 
4. The middle - aged man to whom my father is talking is the director. 
5. The professor whose course I am taking is excellent. 
6. Mr. Smith whom I had come to see said he was too busy to speak to me. 
7. Tom has three sisters, all of whom are married. 
8. I sent him two letters , neither of which he has received. 
9. One of the elephants which we saw at the zoo had only one tusk. 
10. That car whose engine is very good belongs to Dr. C.
11. You sent me a present for which I thank you very much. 
12. Max isn't home yet,which worries me. 
13. Be sure to follow the instructions which they are given at the top of page. 
14. Hoan Kiem lake whose water is always blue is a historical place. 

Có gì sai mong chuyên gia yenpham chỉ bảo ạ

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1. The two young men with whom you are acquainted are not good persons. 
2. My father whom you met this morning goes swimming everyday. 
3. Mary and Margaret whom you met yesterday are twins. 
4. The middle - aged man to whom my father is talking is the director. 
5. The professor whose course I am taking is excellent. 
6. Mr. Smith whom I had come to see said he was too busy to speak to me. 
7. Tom has three sisters, all of whom are married. 
8. I sent him two letters , neither of which he has received. 
9. One of the elephants which we saw at the zoo had only one tusk. 
10. That car whose engine is very good belongs to Dr. C.
11. You sent me a present for which I thank you very much. 
12. Max isn't home yet,which worries me. 
13. Be sure to follow the instructions which they are given at the top of page. 
14. Hoan Kiem lake whose water is always blue is a historical place.