You may be surprised to learn how many animals actually have a memory. 1 your goldfish can show evidence (证据) of learning ability. If you have a pet fish, try this 2. Every day when you feed the fish, sprinkle (撒) the food only in the same location.

    Keep a record of daily observations (观察) of the fish, taking down notes about the fish's swimming directions or behavior whenever you come to feed it. Before long, the fish should swim to the spot where you sprinkle the food whenever you approach (靠近) the tank. See how it reacts (反应) to your approaching the tank and take notes before, 3, and after your experiment.

In this example of animals' memory, we don't really know if your fish knows the fact that you are going to feed it. But it has showed its 4 ability to learn and to remember.

    Bees 5 with each other in a way which shows an intelligent memory. When a bee finds a good location for gathering nectar (花蜜), it will remember 6 to get to this location from its hive (蜂巢). The bee then returns to the hive and passes along its memory by doing a complex dance to inform the others of where the food was found. It uses wings, legs, antennae (触角) and body to deliver the message. When the dance is over, other bees fly to this location to bring back food for the hive.

    A major development to self-driving cars may change the way we will drive in the future. Google, the leading company in self-driving technology, has changed its develop plan. It had driverless cars built by car factories, but now it will start building its own cars.

    Google has started to build some kinds of experimental electric self- driving cars that look like a Smart car or Fiat 500. There is no steering wheel(方向盘), gas pedal or brake. The only things a human passenger controls are a red "e-stop" button (按钮) for fear stops and a start button. The car's only "friendly" face is designed to make it help people accept self-driving technology.

Google workers took part in a long experiment, in which they used self-driving cars for their usual travel to work. No accident happened, but Google's heads realized that depending on a human passenger to drive in an emergency(紧急情况) wouldn't work because they may be reading, working , or sleeping. Now the self-driving car drives by itself if the driver takes his hands off the wheel for over ten seconds.

Google recently announced that its cars had covered 700,000 miles of public roads, and they were now running in busy city streets. People who love self-driving cars say this will improve transport by making roads safer, cutting down accident, and making less pollution.

    Of course, there's no need to look for parking at a crowded shopping mall. Instead, users could let their self-driving cars drop them off to park itself. A mother who took a test ride said that having the car would allow her more time to catch up with her son. The cars could also allow people who might not be able to drive to enjoy the hand-free driving. And drunk driving? Not a problem. It is very likely that by 2020, driverless cars will be common. Do you believe so?

    We cannot stop earthquakes, but we can do things to make sure they do not destroy (破坏) whole cities. First, it is not a 1 idea to build houses along the lines where2of the earth's plates join together. Second, if you think there 3 be an earthquake, it is better to build houses on rock, not on 4. Third, you must make the houses as 5 as possible. Weak buildings will fall down in an earthquake, but strong ones may 6.

    Scientists are 7 that one day an even bigger earthquake will hit the part around S an Francisco. They call it “The Big One”. But people today are still building more 8. The population in and around San Francisco 9 is ten times more than it was in 1906. This means that 10 there is another earthquake, a great many houses and buildings will be destroyed.

    The solar powered bicycle—"Cycle Sol"(太阳能自行车)

A person riding a bicycle uses little energy to make the bicycle move, and there is no pollution at all when you are1. But in some countries most people don't go to work by bicycle because they wouldn't like to spend more time and feel2.

    These3a solar powered bicycle has been invented in England. Persons who ride it may not feel tired, and it's good4the environment.

    The solar-powered bicycle5an electric bike(电动车) but the motor(发动机) runs on a solar energy battery.

    The bright yellow "Cycle Sol" looks like a normal cycle but has a canopy lined with solar cells overhead (可以接受太阳能的天棚装置).

    The bicycle can be left in the daylight to charge(充电), even when the sky is6. You can leave it outside the office during the day to ride to7. These days solar cells are pretty good at8light, so it should still work when the sky is cloudy. 9night, the small battery can be charged using the main electricity in just a few hours. To save energy, when you're peddling up a steep hill, you can turn off the motor. And if10rains, the cell will keep you dry.