public boolean sDown(){
		boolean change = false;
		for(int i =0 ; i < 4 ; i++){
			for (int j = 3 ; j > -1 ; j--){
				//MOVING
				if(mDown(i, j))
					change = true;
			}
			//SUMMING
			if (aDown(i))
				change = true;	
		}
		//GEN A NEW TILE
		if(change)
			genTile();
		return change;
	}