When he was nine years old, American boy Milo Cress had a question: How many plastic straws(吸管) do Americans use every day?

    He quickly learned there wasn't a simple answer. The boy tried to work it out himself. Through lots of research, Cress found out that Americans use about 500 million straws every day. In hopes of reducing plastic waste, he founded the Be Straw Free project in 2011.

    Cress started the project in his hometown – Burlington, Vermont. He asked a local restaurant to stop offering straws with every drink order. It was a simple change. However, it would save money. And by doing that, the restaurant would cut down on its straw use by 50 percent.

    For the years that followed, Cress tried to spread his project across the United States. More and more restaurants agreed to join. They stop providing the customer with a straw unless he or she asks for one. Last April, Seattle became the first American city to completely ban (禁止) plastic straws.

    Plastic pollution has been one of the most serious problems today. According to scientists, more than eight million tons of plastic end up in the ocean each year. Plastic straws are especially terrible. They make it easy for people to get comfortable with single-use plastics.

    After his project became popular, Cress took his findings on the road. He has since spoken to tens of thousands of students around the world. He wants to encourage more people to say no to plastic straws.

    "Focusing(聚焦) on straws is one simple step we all could take," Cress says. "And it makes me feel that I, as a kid, could make a difference, too."

    Mr. Brown has got a dog. Its name is Ben. And the dog is very good to Mr. Brown.

    One hot day, Mr. Brown returned home from work and said to himself, "I want to know where the water jar (罐子) is." Then he found the water jar with clean water. Mr. Brown wanted to drink some water. But the dog barked (吠叫).

    "Oh, Ben! Please be quiet! I will give you some water," said Mr. Brown. But the dog didn't stop barking and even jumped up to him. "What? Let me drink some water first. Then I will give you something to eat," said Mr. Brown. But the dog still didn't stop barking. And the dog still jumped up and even broke the jar at last. Mr. Brown got very angry (生气的). But soon, he found a snake (蛇) in the pieces of the jar. He knew about the snake. It was poisonous. It could be very dangerous for him if he drank the water. Mr. Brown thanked the dog a lot.