如何在PHP中获取数组键的每个值

I have an array after doing theprint_r($arr); like this:

Array
(
   [0] => (orange, lemon, mango)
   [1] => (house, apartment, hostel)
   [2] => (one, two, three)
   [3] => (monday, tuesday, wednesday)
)

当我尝试这段代码

foreach ($arr as $k => $v){
echo $k .'=>'. $v;

}

我得到这样的结果:

0=>(orange, lemon, mango)
1=> (house, apartment, hostel)
2 => (one, two, three)
3=> (monday, tuesday, wednesday)

However, what I would like to get is the the first value of each key, for example, orange, house, one, monday to put into a variable called $var1, and the second to put into an another variable called $var2, and the third to put into an another variable called $var3 respectively so that I can insert them into the MySQL table.

感谢您的帮助。

谢谢,