Then we laid down sheets with electric pads on top of them, then another sheet on top of that, then the sand on top of the that, so the sand covered an area of about three feet.
我们在床单上垫了一层电热垫，再垫上一层床单，最后把沙子辅在最上层，这样沙子总共覆盖了大约3英尺。
2
He stayed for a couple of hours trying to track the culprit down and finally found the beetle, which eats holes in lily pads and zips from one to the other on the water's surface.