Điền vào chỗ trống từ thích hợp

1. The Great Pyramids are more than ........ years old.
2. It is still unknown how the ancient Egyptians ......... 2 million stone blocks.
3. The Statue of Liberty was gifted as a symbol of .......... .
4. To enjoy the full picture of the Statue, you must ......... tickets with a local cruise company.
5. The structure of The Great Wall of China is like a huge ........... .