use strict;
use warnings;

open my $inFH, q{<}, \ <<END or die qq{open: $!\n};
The boy stood on the burning deck,
Eating an ice cream, Walls.
The ice fell down his trouser leg,
And paralysed his left kneecap.
END

while ( <$inFH> )
{
    print qq{$.: $_} if m{([aeiou])\1};
}

close $inFH or die qq{close: $!\n};