"Pointing at the window" 指向窗户。这句话的来源是英语动词 "point" 的常规用法。例如：

She pointed at the window and asked me to open it.

He pointed at the window and said that's where the bird is.

在这些例句中，"point" 表示指着某个方向，通常是用手指来指向。例如：

She pointed at the door and asked me to follow her.

He pointed at the sky and said that's where the plane is.

总之，"pointing at the window" 指向窗户这个动作通常是用手指来完成的，表示指着窗户这个方向。