Sometimes the world may feel like an unhappy place. However, you can make a difference. If you make even a person smile today, you can help make this world a better place. Here is a list of ideas to help you.

Send a handwritten letter

    In this age where everything is sent by email, it is a shock to receive a letter through the post. Writing a few words on paper to a friend is an easy way to make one smile. Even a postcard with a couple of sentences could really make someone's day- all for the price of a stamp！

Volunteer

    Volunteering is one of the nicest things you can do. It requires (需要 ) some time and research to find the perfect project before volunteering. Whether you volunteer at your local youth group or take dogs from the shelters for a walk, the simple fact that you are giving up your time to help someone else is unbelievable. There are so many chances, so you are sure to find one that is right for you. And it doesn't necessarily have to take up all your time-it could be once a week or a couple of times a year.

Make something for a special person

    Whether you're creative or not, taking time to make something for someone else M shows how much you appreciate (感激 ) them. Even if you think you are not creative, the receiver will feel lucky to get such a special gift that you put your time into. Some ideas could include a card, painting, drawing, song, poem or cake!

Tell someone "I love you"

    It can be anyone-a family member or a friend. You don't even have to say "I love you". Perhaps you can tell a friend that you appreciate all they are to you, or remind your mum that you love her. Sometimes, in our busy lives, we forget to take a moment to tell people what they mean to us.

    Sometimes the world may feel like an unhappy place. However, you can make a difference. If you make even a person smile today, you can help make this world a better place. Here is a list of ideas to help you.

Send a handwritten letter

    In this age where everything is sent by email, it is a shock to receive a letter through the post. Writing a few words on paper to a friend is an easy way to make one smile. Even a postcard with a couple of sentences could really make someone's day- all for the price of a stamp！

Volunteer

    Volunteering is one of the nicest things you can do. It requires (需要 ) some time and research to find the perfect project before volunteering. Whether you volunteer at your local youth group or take dogs from the shelters for a walk, the simple fact that you are giving up your time to help someone else is unbelievable. There are so many chances, so you are sure to find one that is right for you. And it doesn't necessarily have to take up all your time-it could be once a week or a couple of times a year.

Make something for a special person

    Whether you're creative or not, taking time to make something for someone else M shows how much you appreciate (感激 ) them. Even if you think you are not creative, the receiver will feel lucky to get such a special gift that you put your time into. Some ideas could include a card, painting, drawing, song, poem or cake!

Tell someone "I love you"

    It can be anyone-a family member or a friend. You don't even have to say "I love you". Perhaps you can tell a friend that you appreciate all they are to you, or remind your mum that you love her. Sometimes, in our busy lives, we forget to take a moment to tell people what they mean to us.

Okay to Eat?

    At least 50% of U.S. adults have eaten food off the floor. That's according to a 2017 Harris Poll. Many people use the five-second rule. The rule says that fallen food is safe to eat if it has been on the floor for less than five seconds. Can people really use the five-second rule to save a dropped sandwich? Or should they throw it and make a fresh one?

    Donald Schaffner is a professor of food science. His study shows that the five-second rule should not always be used. In his 2016 report, he says it's not wise to eat dropped wet food. The wet food takes in bacteria (细菌 ) as soon as it falls. "Bacteria don't have legs, they move with the moisture," Schaffner says. The wetter the food is, the more bacteria it soaks up(吸收) .

    Anthony Hilton studied the five-second rule too. He is a professor of Life and Health Sciences.

    Hilton found that a dry food on the floor collects fewer bacteria than a wet food. Hilton also found that carpeted floors pass fewer bacteria than wood floors. Still, one should be careful. "Food that is on the floor is never completely risk-free to eat," he says. "But if you drop a dry food in your house, it's usually okay if you pick it up very quickly. Most clean homes don't have bad bacteria."

    Should you eat food that was dropped on the kitchen counter? Dr. Steven Dowshen is a doctor for children. He says that floors are not the only place that can make food unsafe to eat. "Kitchen counters can contain more harmful bacteria," Dowshen told TFK. This is because raw foods sometimes have bad bacteria called salmonella. These raw foods can be on kitchen counters. "If people eat food off a surface that has salmonella, they can get very sick," says Dowshen.

    With the five-second rule, the type of food and the place where it falls matter. So perhaps use this e instead: When in doubt, throw it out.

    Rik-rrork. That's the sound made by frogs singing at night. You might have thought the noises were just the musical sounds of ure. You probably didn't realize that you were listening to frogs' communicating with one another. These familiar sounds are not random(随意的) but are actually meaningful to frogs.

Being Heard but Not Seen

    Frogs are good at being heard but not seen. These animals have several characters that protect them n predators (捕食者 ). One is their size. Most frogs are small, which helps them hide easily. Many frogs have coloring that allows them to hide in their environment, making it difficult for predators to find them. In addition, most frogs are active at night. So it is difficult for most animals to see them in the dark.

Small but Loud

    Frogs call to tell other frogs where they are. Their voices can be very loud. But when frogs feel the footsteps of a larger animal, they become silent.

    Many of the world's frogs live in rain forests, where there are many different animals calling to their own species (物种 ) in their own ways. Frogs need to call loudly enough to be heard through the noise in order to find other frogs.

Singing with Purpose

      Peter Narins is a scientist who studies how frogs call to one another. He has learned that frogs use their calls to help them tell friend from enemy. They sing the same notes at the same volume (音量 ) each time they call. In addition, Narins has found that frogs of the same species always sing the same patterns (模式 ). These patterns are like a code that is different from other animals' calls and difficult for others to copy. Narins also observed that timing plays a role in frog calls. Many frogs call only at a certain time of night.

More Work to Do

    Scientists want to better understand the purpose of frog calls. Studies continue to explore the details of frogs' unique communication. Being heard but not seen is one way frogs stay safe. The idea that they have found a way to survive in a dangerous world is simply amazing.