Dưới đây là các câu hoàn chỉnh được sắp xếp theo yêu cầu:

1. Phong Nha - Ke Bang is one of the most spectacular National Park wilderness sites in South East Asia and one of the second largest limestone regions in the world.

2. Son Doong Cave was discovered in 2011 by a British caving team and explored in 2009, and now open to a limited number of tourists since 2014.

3. Ha Long Bay is probably one of the most fabulous natural wonders in Vietnam.

4. Hue, once the capital of Vietnam, was the emperors’ location, and it’s an amazing place to visit for its history lesson.

5. Ha Noi is, and you’ll find Vietnam's capital city at the banks of the Red River with Hoan Kiem Lake right at its heart.