1)I've never seen a higher buiding than this.
2)Linh prefers the countrylife to the citylife
3)Mr.Ba's car is the biggest car in the company
4)We haven't met uncle Tam for three years
5)We don't have to drive so fast
6)It is 3 years since we last went to my son
7)Trung went to Sapa by train last Sunday
8) It will not be unneccessary for you to go to the meeting tommorrow
9)When did he buy the computer?
10)It's first time I have talked to the headmaster
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