①come ____     

②swim ____     

③skate ____     

④run ____     

⑤write____     

⑥have____  

如图所示，A、B为两块水平放置的金属板，通过闭合的开关S分别与电源两极相连，两极中央各有一个小孔a和b，在a孔正上方某处放一带电质点由静止开始下落，若不计空气阻力，该质点到达b孔时速度恰为零，然后返回．现要使带电质点能穿过b孔，则可行的方法是（   ）

    What do you think the future will be like? Here are some answers from some students.

    Mary: Everyone will have a computer at home. There will also be many machines in the future. Then people will work only two or three days in a week.

    Jack: The weather in the future will be very hot. People can't live on the earth. They will have to look for (寻找) another planet to live on.

    Linda: I think the life in the future will be nice. There will be a lot of flowers and trees. And cities will look like parks.

    Henry: Every family will have a family doctor, so people will be seldom ill (很少生病) They will live to 120 years old.