Five hundred years ago, potatoes grew in South America. They were an important food for the people who lived in these high mountains. In other parts of the world, however, people didn't know about potatoes.

    The Spanish came to South America in the 1500s. They learned of potatoes and took some back to Spain. By 1570, people grew white potatoes in parts of Spain. By 1580, people in Italy were also growing potatoes.

    From Spain, potatoes travelled to France. In France, however, people were afraid to eat this new vegetable. They thought it was bad for health. Then the King of France tried to make his people eat potatoes. But for many years, the French still refused to eat potatoes.

    Potatoes reached England in a different way. In 1586, the English explorer(探险家) Drake stopped in Colombia. There he probably picked up some potatoes and took them back to England. At first, the English refused to eat potatoes, too. They used potatoes to feed their pigs and chickens.

    From England, the potato travelled to Ireland. The potato grew well in the poor soil of Ireland and soon it was an important food for the people in Ireland.

    In the early 1700s, Irish people brought potatoes to North America. By 1750, many people in New England were growing and eating potatoes.

    We have known for a long time that flowers of different plants open and close at different time of day. Yet no one really understands why flowers open and close like this at special times. It is not as simple as we might think, as new experiments(实验) have shown. In one experiment, flowers were kept in darkness. We might expect that the flowers, without any information about the time of the day, did not open as they usually do. In fact, they continued to open at their usual time. This shows that they have some mysterious (神秘的) way of knowing the time.

    Their sense of time does not depend on information from the outside world; it is, so to speak, inside them, a kind of “inner clock”. This discovery may not seem to be very important. However, it was later found that not just plants but also animals including man have this “inner clock”which controls(控制) working of their bodies and their activities.

    Human beings, then, are also controlled by this mysterious power. Whether we wish it or not, it affects such things in our life as our need for sleep, our need for food. And our ability to concentrate(集中).

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    Every minute，someone is setting up an Internet company somewhere, in the world． Each one is searching for the one great idea that could make his web company click in a big way．And they are trying all kinds of tricks to attract people towards their websites．While some websites offer sounds，cartoons and amazing photos on screen to make their sites almost a movie-like experience for the viewers，others provide free downloads and competitions．

    A company in California，US，has decided to offer online smells to people who visit its website．

    That is，if a pizza image comes on screen，your nose will catch the smell of bread and cheese！All you need to do is to connect a device（设备）called “iSmell” with your computer．This smart little device contains（包含）some chemicals that can create different kinds of smells．

    The company has invented software that changes the chemical composition（成分）of different smells into digital signals(数字信号）．An onscreen image，which is programmed with the proper digital signal，will start the“ iSmell" device．The device will use the software to change' the digital signal again and let go of the correct smell．This device reads the digital smell code（代码）from the website and creates the proper smell from its store of chemicals．This smell is then made to blow softly in the direction of the user with the support of a small fan．

    In order to let go of the correct smell，the company has created a “Scent Registry”，which contains a digital index of thousands of smells．The company plans to allow website developers to integrate（合成）the proper smells in digital code to their games and images．The company is also hoping that Hollywood filmmakers will use the smell technology in their movies．Imagine audiences getting the smell of rocket fuel as a spacecraft takes off on the cinema screen！Of course，filmmakers will have to be careful not to shoot in dirty neighborhoods，which have a lot of rubbish lying around．

    April will bring a new product– the Apple Watch into the market. Last week, the watch was firstly introduced by Tim Cook, Apple's CEO. The price of the watch is from $349 to $1,099, depending on its size and whether it is a sports or regular one. Apple engineers and designers have put in a lot of thought and hard work into creating this small screen on your wrist. The sensor(传感器)on the screen not only finds your finger, but also knows the difference between when you are tapping(轻触), and when you are pressing harder.

    The watch also has haptic feedback(触觉反馈). You can send personal messages to your friend —such as drawing a star or a special sign with your fingers, or tapping the watch, say 3 times, and your friend will receive those taps on their wrist.

    Besides telling the time, the watch will use 'Bluetooth' to connect with your iPhone and show calls or text messages that come in.

    According to Tim Cook, the watch may open up a whole new area of applications（应用） that we had never thought of. Some car factories like BMW have developed an app that allows its car owners to open their cars with the watch. A 'Hotels' app may allow you to open the door to your hotel room without worrying about losing the smart-card. And finally, even at the airport—passengers may be able to simply wave their wrist to check into their flight.

    The biggest use of the watch, however, is as your personal fitness coach. The watch can show your pulse (heartbeat) using a sensor at the bottom of the watch. It also has the same sensor as your iPhone, so it knows when you are moving, and also how much you are walking or running. It will remind you if you have been sitting for too long without taking exercise.