Removing elements from associate array.

Elo!

I've got a problem with removing elements from associate array (php). Above
you'll find a schematic structure of my array:

ARRAY
------
-> ELEMENT1
--> KEY1 => VALUE
--> KEY2 => VALUE
-> ELEMENT2
--> KEY1 => VALUE
--> KEY2 => VALUE
-> ELEMENT3
--> KEY1 => VALUE
--> KEY2 => VALUE
-> ELEMENT4
--> KEY1 => VALUE
--> KEY2 => VALUE

A script I try to prepare is going to remove a single element from this
array leaving others "unharmed" :). If an array consists of only one
element - that's ok, it is removed. If there are two records in an array, a
try to delete second element throws off first one. The more elements in an
array, the more mistakes occurs. I think that the problem is to find an id
of an element (ex. ELEMENT2) (this is the element, that was identified in an
foreach{} loop as an element to remove). I'm sure the solution is very
simple, but i can't get it on (i'm not sure if this word construction is
correct - i am not a native english speaking person). I was looking for the
solution in some sources, but the only thing i have learnt is that to remove
an element from an array is used a unset() command. That's correct - but
how to get an id for an element to remove. If I could ask you to give me an
example of deleting, let's say, second element from the structure i wrote
above.

MaciejK