User-agent: *
Allow: /
User-agent: spider1
Crawl-delay: 20
Allow: /
User-agent: spider2
Crawl-delay: 20
Allow: /
User-agent: spider3
Crawl-delay: 20
Allow: /
User-agent: Slurp 
Crawl-delay: 20
Allow: /
User-agent: MSNBot 
Crawl-delay: 20
Allow: /