Anne Sullivan tried to teach Helen Keller, who was blind and death, language. It was very hard. When She tried to teach Helen that sometimes words have two different names, or sometimes there are same names for different words.
Helen wouldn't accept that even though their were two different things, they were called the same thing. She thew the doll to the ground in anger.
Anne brought Helen a mug, and told her it was a mug. Then she let Helen feel the water in the mug and told her it was water. Helen was confused again, so Anne took her to the water well, and then taught her that the liquid was water, and the cup was the mug.