代碼寫完了，可是不能實(shí)現(xiàn)循環(huán)生成， 求解這是為什么

//?JavaScript?Document
var?fruitObj?=?function?()
{
	this.alive?=?[];
	this.x?=?[];
	this.y?=?[];
	this.l?=?[];
	this.spd?=?[];
	this.fruitType?=?[];
	this.orange?=?new?Image();
	this.blue?=?new?Image();
	
	}
fruitObj.prototype.num?=?30;
fruitObj.prototype.init?=?function()
{
	for(var?i?=?0;?i?<?this.num;?i++)
	{
		this.alive[i]=?false;
		this.x[i]=0;
		this.y[i]=0;
		this.spd[i]?=?Math.random()?*?0.017?+?0.003;
		this.fruitType[i]="";
		}
		this.orange.src?=?"./src/fruit.png";
		this.blue.src?=?"./src/blue.png";
	}
	
	
	
fruitObj.prototype.draw?=?function?()
{
	for(var?i?=?0;?i<this.num;i++)
	{
		//draw
		//find?an?ane?,?grow,?fly?up
		if(this.alive[i]){
			if(this.fruitType[i]?==?"blue")
			{
				var?pic?=?this.blue;
				}
				else{
					var?pic?=?this.orange;
					}
			if(this.l[i]<=14)
		{
			this.l[i]?+=?this.spd[i]?*?deltaTime;
			}
			else{
				this.y[i]?-=?this.spd[i]?*?7?*deltaTime;
				}
		ctx2.drawImage(pic,this.x[i]-this.l[i]*0.5,this.y[i]-this.l[i]*0.5,this.l[i],this.l[i]);
		
		if(this.y[i<10])
		{
			this.alive[i]?=?false;
			}
		????}
		
		}
	}
	
	
	
fruitObj.prototype.born?=?function(i)
{
	var?aneID?=?Math.floor(Math.random()*?ane.num);
	this.x[i]?=?ane.x[aneID];
	this.y[i]?=?canHeight?-?ane.len[aneID];
	this.l[i]=0;
	this.alive[i]?=?true;
	var?ran?=?Math.random();
	if(ran?<?0.3)
	{
		this.fruitType[i]?=?"blue";
		}
		else
		{
			this.fruitType[i]?=?"orange";
			}
	
	}

	
function?fruitMonitor()
{
	var?num=0;
	for(var?i?=?0;?i<fruit.num;?i++)
	{
		if(fruit.alive[i])?num++;
	}
	if(num<15)
	{
		sendFruit();
		return;
		}
}
function?sendFruit()
{
	for(var?i=0?;?i?<?fruit.num;?i++)
	{
		if(!fruit.alive[i])
		{
			fruit.born(i);
			
			return;
			}
		}
	}	
	
fruitObj.prototype.update?=?function()
{
	var?num?=?0;
	for(var?i?=?0;?i<this.num;i++)
	{
		if(this.alive[i])?num++;
		}
	}