Tree Planting Day is an important day in the world. Today, many countries have such a holiday. In China, Tree Planting Day is on March 12. It is a day to remember Sun Yat-sen. Sun Yat-sen was a great person in China. However, few of us know that he was the person who encouraged people to plant trees in China.

Tree Planting Day in China was started in 1915. From 1916 to 1928, Tree Planting Day was celebrated on the Chinese Qingming Festival each year. Sun Yat-sen asked people to stop cutting down forests in many of his books and speeches. He even planted trees himself with many people. Sun Yat-sen died on March 12, 1925. In order to remember Sun Yat-sen, Chinese people decided to set Tree Planting Day on March 12 every year.

Planting trees is good for our Earth. Trees can not only make the environment beautiful but also give us forests, stop soil from losing, protect farmland and change climate. They can make the Earth a good place for us to live in. Without trees, our lives will be difficult. For example, we can’t get fruit or oil from trees. Therefore, it’s important for everyone to plant more trees on Tree Planting Day.

There’s no question that Americans love both dogs and cats. About 48 percent of families in the U.S.own dogs and 38 percent own cats. But one thing many people can’t agree on is which animal makes a better pet.

Cat lovers say their pets are easier to care for than dogs. They point out that cats don’t jump on visitors. Also, it’s cheaper to own a cat. Cat owners spend $ 300 to $ 800 less a year than dog owners do. Besides, dogs mess up the house by chewing(咬) things like shoes.

Still, dog owners say the money they spend is worth it. They argue that dogs are more social than cats. Also, scientists say that dogs are smarter than cats. Dog lovers point out that dogs help people, too. For example, dogs can be trained as service pets for people who are disabled.

Here’s what two kids think.

I have both cats and dogs, but I’d rather own a cat at any time. Dogs are noisy and make a mess. Cats are much quieter, and they’re better companions(伴侣).Cats are the perfect size for sitting on my knees. Also, it’s easier to take care of cats.

Michelle, 12, New York

There are many reasons why dogs are called “man’s best friend”. They are playful and love their owners, and you can teach them cool tricks. Cats mostly just care about eating and sleeping. Also, dogs can be service pets and even lifesavers. A cat isn’t going to protect your home from burglars(窃贼).

Logan, 14, Washington D.C.

People all over the world use colorful little squares of paper to help them remember something. Some people even use them to create works of art: These little squares are called Post-it Notes. One of their creators, Spencer Silver, recently passed away at 80.

Silver first started working on the notes in 1968, when he was working for technology company 3M. He discovered a kind of weak glue (胶) that didn’t leave behind any residue (残留物) when it was taken off. ★ But he and his partner Art Fry came up with the idea of putting the glue on small pieces of paper to create notes that could be easily moved from one place to another. They borrowed some yellow paper and went to work on their creation. The Post-it Note was finally born in 1974.

However, it wasn’t brought to market until 1977 and didn’t really take off until 1980. Today, it is one of 3M’s best-selling things. The company makes more than 50 million Post-it Notes every year. Silver, a creative chemist, had 37 inventions during his time at 3M. He was included into the National Inventors Hall of Fame for his achievements.

These days, Post-it Notes are made in many different colors. sizes and shapes, including fruit and animals. They are useful for many things. You can use them to take notes, mark your place in a book, give someone a reminder, or even ask someone to a dance. You can even see them in the Museum of Modern Art in New York.