The numbers from one to twenty in English are: one, two, three, four, five, six,seven, eight, nine, ten, eleven, twelve, thirteen, fourteen, fifteen, sixteen, seventeen, eighteen, nineteen, twenty. From 21 to 99, the tens place is formed by adding the suffix “-ty” to the ones digit, except for the special forms: twenty, thirty, forty, fifty, eighty. The numbers sixty, seventy, and ninety are formed by adding the suffix “-ty” to the ones digit. To express a number between 21 and 99, we use a hyphen between the tens digit and the ones digit.