完形填空People and a lot of animals live on land.But almost thre

完形填空
People and a lot of animals live on land.But almost three quarters of the earth is w___1___.Fish and many o___2___ sea animals live in the rivers,lakes and seas.
It’s a wonderful world u___3____ the water.Whales（鲸) are the largest animals on the earth.Dolphins(海豚) are the cleverestanimals,and they all l___4___ in the seas.
You can f___5___ many sea animals and plants in the seas.They are in different colours,and they are very b___6____.
The seas give us very good things to enjoy.They a__7____ give us food to eat
and oil (油) to burn (燃烧).In some places,people get drinking water f___8___ sea water.The seas are i____9____ to all the animals in the world.We must keep them c___10___.