There is one mistake in each sentence, try to find the mistake and correct it

There is ONE mistake in each sentence, try to find the mistake and correct it.

1.   The Royal Palace is one of the largest palace in Europe.

2.   "Have you ever eat Ha Noi Pho, Steven?"

3.   Up to now, I have visited Da Lat third times.

4.   Do you think the most popular Vietnamese writer of children is To Hoai?

5.   Sydney Opera House is an UNESCO World Heritage building.

6.   The Merlion is a creature with the head of a lion so the body of a fish.

7.   New York is an excited city with many skyscrapers.

8.   You can play boating on the West Lake and it is very nice.

9.   I have been to the beaches in Nha Trang many time with my family.

10. Is Chicago or Los Angeles the two biggest city in the United States?