03-06-2015 07:00

In Japan, ships near Tokyo Bay had to move carefully because killer whales swam through the area. People want to be careful because ships collided with whales and other animals in the bay. It is rare to see killer whales in this area.

The killer whale is also called the orca whale, and it lives in all oceans, including the freezing Arctic and Antarctic and the tropical seas.

They are hard to count because there are so many of them, but the estimate is that there are 50,000 in the world.

Difficult words: collide (to crash into), rare (something that does not happen often), estimate (a guess which somebody makes about the number of something).

You can read the original story and watch the video in the Level 3 section.