It would be easier to work with an "array of arrays", rather than 4 separate arrays.

my $s=q|Tom.Dog.Ben.Cat|; 
my @array; 

for (split /\./,$s){
  push @array,[$_]
}

# Created a 2-d array containing:
#   [0][0]=Tom
#   [1][0]=Dog
#   [2][0]=Ben
#   [3][0]=Cat

print qq| $array[2][0];\n|;
# Prints "Ben;"
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