#!/usr/bin/perl

my $flag;


while(<DATA>){
  if (/^({\w+})/) {
    $flag = $1;
  }

elsif ($flag =~ m/{TAG}/){
         print $_;
}
elsif ($flag =~ m/{ID}/){
         print $_;
}
}

__DATA__
{IT} 343
1
{DATE}
090104
{LINE}
LEGISLATORS  VISIT SENIOR APARTMENT COMPLEX
{TAG}
1lutherridge0104.ART
{ID}
234
{IT} 434
2
{DATE}
090104
{LINE}
LEGISLATORS  VISIT SENIOR APARTMENT COMPLEX

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{IT} is the start of one file. How to print the {IT} line if both {LINE} and {ID} doesn't exists.

In reply to print line by Anonymous Monk

Title:
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and:  <code> code here </code>
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