What is the biggest island in the world?
Greenland.
What is this?
waterfall
In which of them water is saltier? In the lake or in the sea?
In the sea.
What is this?
river
What is drier? The field or the desert?
The desert.
Which is higher? The mountain or the hill?
The mountain.
What is this?
Island.
What is this?
lake
What is the largest country in the world?
Russia.
What is this?
beach
What is this?
Desert.
What is this?
mountain
What is this?
sea or ocean
Which is wider? The river or the stream?
The river.
What is between the mountains?
valley