根据短文内容，判断下列各句正误。
      Hong Kong has about forty public beaches. Some of them are very famous around the world. People can go there for a swim. You can go to them by bus. To go to some beaches you must take a boat.
    You will swim there without danger if you remember these instructions:
    Never swim alone.
    Never go out in a boat if you cannot swim.
    Never swim after a meal or when you feel hungry or tired.
    Don't stay in the water too long.
    Remember: A red flag means that it is dangerous for anybody to go into the water. A blue flag means that it is dangerous for children.

对两个大小不等的共点力进行合成，则（   ）

欧洲西部的国家从中东进口石油，油轮走最短航线，必须经过的海上通道是（    ）