Choose the options that best complete the passage. Sơn Đoòng Cave Sơn Đoòng Cave is (36)___________ at the heart of Phong Nha Kẻ Bàng National Park in Quảng Bình Province. It was originally discovered in 1990 by a local man named Hồ Khanh while he (37)___________ for timber. When he peered inside the opening of the cave, he saw clouds and heard the sounds of a river. (38)___________, he didn’t dare to go any further. The cave stayed unknown to the rest of the world until Hồ Khanh found its ...

Choose the options that best complete the passage.

Sơn Đoòng Cave

Sơn Đoòng Cave is (36)___________ at the heart of Phong Nha Kẻ Bàng National Park in Quảng Bình Province. It was originally discovered in 1990 by a local man named Hồ Khanh while he (37)___________ for timber. When he peered inside the opening of the cave, he saw clouds and heard the sounds of a river. (38)___________, he didn’t dare to go any further. The cave stayed unknown to the rest of the world until Hồ Khanh found its entrance again in 2008. Later, he (39)___________ the way for a British expedition to explore it. In 2010, it was officially announced that Sơn Đoòng was (40)___________ largest natural cave in the world, (41)___________ to house an entire New York City block. The cave is home (42)___________ rare fauna that can (43)___________ be found anywhere else. (44)___________ fossils were also found in the cave. As tours to Sơn Đoòng gain in (45)___________, hopefully the unique natural system will still unchanged.