You are walking down the street. Suddenly it starts to rain and you don’t have an umbrella. What do you do? Run or walk?

Most people would rather run because it will get you out of the rain faster. But if you run, you also run into more raindrops. So, what should you do?

Things are more complicated (复杂的) than you might think. Franco Bocci, a professor at the University of Brescia in Italy, found that whether you should travel slowly or quickly in rain depends on the wind direction and your body shape, according to the BBC.

When there is no wind, and the rain lands directly on you, Bocci suggests that you should run and hide as fast as possible. But if the wind comes from behind and blows the rain onto your back, the best thing to do is to walk at the same speed (速度) as the wind. This way, both your front and back will stay mostly dry.

This is not all. When the wind blows in from the side, you’ll have to think about one more thing—your body shape. Thinner people are hit by fewer raindrops. In this case, a fatter person had better run while a thinner person should still try to match their speed to the wind.

“In general, the best thing is to run, as fast as you can—not always, but in general.” Bocci told BBC News, “If you’re really thin, it’s more probable that there will be a best speed. Otherwise, it is better to run fast.”

Now you know what to do next time the rain catches you in the middle of the street. But the best way to stay dry is still to carry an umbrella.

Touch is one of the most important of five senses. It is also one of the fitst senses we develop. If a person is in a hard time, he can choose to cry, talk or eat to get better. But the greatest help for him may be a hug given by friends. A hug is not only one of the most commonly accepted forms of touch but also one of the first experiences we have in the world!

There is no better way for people to understand the importance of hugs than to lose them. If you have experienced the loss of hugs once, you will know how important they are to share.

A recent research has shown that when people hug, the brain releases the chemical（化学物质）which increases our willingness to trust and reduces fear. It has also shown that hugs are great for your heart.

In 1995, a pair of newly born twins was being cared for in hospital. While one of the twins seemed quite healthy, her sister was not. After trying different medical treatments, the nurse on duty, Gayle Kasparian, placed the twins in bed together. The twins immediately snuggled（依偎） up to each other. As one placed her arm around the other, the weak baby became better gradually. How great the power of a hug is!

________, though we are less willing to give them. But Research on people of all ages has shown that a hug is necessary for physical and mental health.

Without hugs we can become sad. A hug provides safety and gentleness. A hug provides us with a sense of health and a feeling of importance and belonging.

3-D films are not new. They first appeared in 1903. The inventors wanted viewers to feel like they were really inside the film they were watching! When you watch a 3-D film, you feel as if the people on the screen are close enough to touch and that the airplane flying at you is flying right off the screen. To watch 3-D films, you may need to wear special glasses. Usually, people buy or borrow the glasses in the cinema. But have you ever thought of making one pair by yourself?

Here are tips for making your own 3-D glasses.

Next time when you go to watch a 3-D film, don’t forget to take your own handmade glasses!