I have this code:

```
public Scene onLoadScene() {
    Random randomGenerator = new Random();
    pX = randomGenerator.nextInt(CAMERA_WIDTH);
    Sprite snow = new Sprite (pX, 1, 30, 30, mTextureSnowRegion);
    scene.getLastChild().attachChild(snow);
    return scene;
}

```

I am trying to make a snowfall. I was trying to use a MoveModifier, but nothing is work.
Please help.