①You want to go out. You made a plan and paid attention to the weather report. Even so, your plan was still influenced by bad weather. The weather report might have told you that it would be “mostly sunny” over the weekend. However, the rain didn’t care about the report at all.

②Everyone has had a similar experience at one time or another. But why is it so hard to predict(预测) the weather?

③Well, although weather reports often go wrong, this doesn’t happen as often as you might think. In fact, a five-day weather report is pretty accurate(准确的). The weather reports are right about 90% of the time. For a seven-day report, the numbers go down to about 80%. For a ten-day report, you have around a 50% chance of things going right. Over that, well, believe the weather report at your own risk.

④Making a weather report is not easy. A lot of data(数据) are collected and studied. Powerful computers use the data to make predictions.

⑤So where do things go wrong? We use the weather today to decide what the weather may be like tomorrow. In this process(过程), many factors may change. These include wind, temperature, and others.

⑥This is why it is often hard to predict the weather. What we can do is to collect more data and improve the accuracy of our data. We can also use better computers and improve the resolutions(分辨率) of our atmospheric imaging(大气成像).

⑦Don’t lose heart. Making weather report may never be a perfect science, but it is always getting better, for our weather scientists are really trying their best.

Have you ever walked into a room and realized you couldn’t remember what you were looking for? We seem to do this more when we are thinking of a few things at once or doing two things at the same time. Some people call this dual-tasking.

Have you ever crossed the road while chatting to a friend at the same time, or walked across a room while answering a phone? That is dual-tasking. Everyone does it and we tend to get better at it as we get older and learn new skills.

But while our brain is a truly amazing computer—more powerful than any real computer, it can only use so much mental energy at one time. Think of your brain as a power station, providing electricity for a number of cities. If some cities need a lot of energy (by having all their lights on), other cities would have less power to work with. There’s only so much electricity to go around.

For young kids, dual-tasking is possible. However, some studies suggest that it can be a little more difficult to younger kids compared with older kids. Why? The power station in their brain is a little smaller and is not producing quite the same amount of energy as older kids.

So why do I sometimes forget to say something before I say it?

The answer is that you are likely to have been dual-tasking just before speaking. It might be because you were thinking about the words you wanted to say and something else at the same time. Sometimes your brain just can’t do two complicated (复杂的) things at once. You may not have enough mental energy at that moment.

Forgetting things is normal for everyone and can happen when you are doing too many things. When it happens to you, don’t be nervous!

Ink wash painting (水墨画) is an old and beautiful Chinese art. This special drawing technique is created with a brush, dipped into ink, then in water before being painted onto rice paper or silk. As you can see, the paintings are created just in black and white. It is said that the technique was invented by an artist named Wang Wei.

Ink wash paintings often feature trees, flowers, landscapes, animals, birds and people. Also, they often go with Chinese poems. The painting style does not put high importance on a precise description of a real scene or object. They are often improvised (即兴的) works from beautiful scenery (风景). Therefore, this type of painting is hard to copy. Today there are many new Chinese artists that use the traditional Chinese ink wash technique to draw new sceneries and pictures.

The first ink wash animation (动画) in China came out in 1960. It’s called Little Tadpole Looking for Mummy. All the animals, plants and rocks in the film are drawn with ink and brush. The film is about 15 minutes long. But it took lots of work. Without computers, the artists had to draw everything by hand. One second of animation needs 24 pictures! Little Tadpole Looking for Mummy won prizes at home and abroad. From then on, ink wash painting and animation becomes more popular in China. People in the world get to know more about ink wash since then!