fly up and down

As you fly up and down the river, you'll see a lot of people have already abandoned their houses and moved to higher ground.

当你在河流中飘来飘去，你会看到很多人放弃了自己的房子，搬到地势较高的地方。

There were two buttons on the remote controller, one was to make the plane fly up and down and the other was to make it circle in the air.

飞机遥控器上有两个键，一个可以使飞机上下飞，一个可以让飞机在空中旋转。

The birds fly up and down happily, just like small black seaplanes. Besides them, the arrival of the wild ducks, at much higher speed, is almost majestic.

湖上的鸟儿，快乐地上下翻飞，恍如成群的黑色水上小飞机，忙个不停，除此之外，飞来的野鸭子速度相对迅捷得多，极为壮观。