①同一数列的任意两项均不可能相同；

②数列－1，0，1与数列1，0，－1是同一个数列；

③数列中的每一项都与它的序号有关．

如图是三峡船闸的工作示意图：打开图乙中阀门B，闸室与下游水道构成一个 ____．从甲到乙的过程中，若以闸室中的水面为参照物，在这一过程中轮船是 ____（填“静止”或“运动”）的．

    In our city there are more and more cars and buses on the roads. Many people drive to work .First, it's good to have a car. You needn't to wait for the bus. You can go to work on time. Then ,there are many busy roads in the city . Can you drive safely? Traffic lights are very important. You must look at the traffic lights and wait for the green man. If someone is crossing the road, you must stop your car and look carefully. We must follow the rules and stay safe on the road.

如图表示某生态系统中四种生物的相对数量关系，这些生物构成了一条食物链，在这条食物链中物质和能量流动的方向是（  ）