1. The country is beautiful

=> It's a beautiful country.

2. Vietnam has a lot of beautiful beaches

=>There are a lot of beautiful beaches in Vietnam.

3. The Amazon River is longer than the Mekong River

=>The Mekong River is shorter than the Amazon river.

4. No boys in my class is taller than Nam

=>Nam is the tallest in my class.

5. What is the height of the Eiffel Tower ?

=> How high is the Eiffel Tower ?

6. What is the population of Ha Noi ?

=>How many people live in Ha Noi