PHP函数变量传递 - PHP Function Variable Pass Through

Rusty，只是简单地尝试通过参数传递内容。我做错了什么？

//Insert into DB
function insert(x,y,z)
mysql_query("INSERT INTO x (y)
VALUES ('z')");

insert("test","name","Tyler");

function insert($x,$y,$z){
    mysql_query("INSERT INTO ".$x." (".$y.") VALUES ('".$z."')");
}
insert("test","name","Tyler");

确保通过$:正确引用变量

//Insert into DB
function insert($x, $y, $z)
{
    mysql_query("INSERT INTO $x ($y) VALUES ('$z')");
}

insert("test","name","Tyler");