Turn these sentences into active voice

2.  Turn these sentences into active voice.
 

4. Lots of souvenirs inside the Temple of Literature are sold.

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     5. The Temple of Literature is considered as one of the most important cultural and historic places/ in Viet Nam.

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     6. Many precious relics are displayed in the Temple of Literature.

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     7. The Temple of Literature is located in the centre of Ha Noi about 2 kilometres west of Hoan Kiem Lake.

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     8. The Imperial Academy was used to educate young men for the country.

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     9. Students at The Imperial Academy are selected from local examinations.

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     10. In 2010, the 82 Doctors' stone tablets were recognized as a memory of the World.

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     11. The first Doctors' stone tablets were erected in 1484.

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     12. The Temple of Literature is surrounded by old trees.

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     13. Minh Mang tomb was started constructing in 1842 and was complete three years later.

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     14. Papers at the Royal examinations in the past were passed by the King.

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     15. Chu Van An was invited to become the principal of the Imperial Academy by Emperor Tran Hien Tong.

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     16. During that period, 2,323 doctors graduated from The Imperial Academy.