100 - one hundred (200 - two hundred; 300 two hundred; 300 - three hundred; )
hundreds of books
1,000 - one thousand (2,000 - two thousand: )
thousands of pupils
1,000,000 - one million (2,000,000 - two million;)
millions of people
1,000,000,000 - one billion (2,000,000,000 - two billion; )
billions of stars
