Read the passage and fill in the blanks with proper words

Do you like to watch whales swimming in the sea? Most people d________, I think. Many people think that whales are f________. In fact they are not fish; they are the biggest animals in the world. But they live in the w________. They swim very fast and can stay under the water for a long time. Of course they also n________ air. This is why they sometimes come out of water. Whales can't l________ in rivers, but in seas or oceans.