1complete the crossword.
across
1 a long line of very big hills
4 a long turning flow of water
5 an area with a lot of trees, plants and animals
8 an area with a lot of sand, but not many plants and
almost no water
9 a piece of land with water all around it
down
2 an area between two hills
3 similar to 5 across, but here it rains a lot
6 an area next to the sea with sand, where some
people go to spend their holidays
7 a big, cold area that covers the land and sea around
the north and south pole