Lucy gets "on the B" - the letter "B" - "bus to downtown and" shows her "bus pass to the bus driver." 露西乘“B”—字母“B”—“路公共汽车到市区，”她“向巴士司机出示了公车月票”。

Your bus pass is like your subway pass. 公车月票就像你的地铁通行证。

In this case, you show the pass to the driver; the driver looks at the pass to see that it is a good pass. 在这种情况下，你向司机出示公车月票;司机看一看公车月票，看月票是否有效。

Lucy then sits "down near the front of the bus and three more people get on board." 然后，露西在“公交车的前面”坐了下来，“这时又有三个人上车”。

On board, "board," means to be on a plane, or a train, or a bus, or a ship. “On board”(board)指的是在飞机、火车、公共汽车或轮船上。

You may say, "I need to get on board my plane," that means you need to get onto your plane - you need to go into your plane. 你可能会说，“我需要上飞机，”这意味着你需要登上飞机——你需要进入飞机。