绕口令。
让我们来说绕口令吧。看谁的舌头最灵活，说得又快又好。Have a try!
1. Thirteen is thirteen, thirty is thirty. Thirty is not thirteen, thirteen is not thirty.
2. Fourteen is fourteen, forty is forty. Forty is not fourteen, fourteen is not forty.
3. Fifteen is fifteen, fifty is fifty. Sixteen is sixteen, sixty is sixty. Seventeen is
    seventeen, seventy is seventy. Eighteen is eighteen, eighty is eighty.
    Niteteen is nineteen, ninety is ninety.
    Don't say 19 is ninety or 90 is nineteen.

参考答案：
“略”

绕口令。
让我们来说绕口令吧。看谁的舌头最灵活，说得又快又好。Have a try!
1. Thirteen is thirteen, thirty is thirty. Thirty is not thirteen, thirteen is not thirty.
2. Fourteen is fourteen, forty is forty. Forty is not fourteen, fourteen is not forty.
3. Fifteen is fifteen, fifty is fifty. Sixteen is sixteen, sixty is sixty. Seventeen is
    seventeen, seventy is seventy. Eighteen is eighteen, eighty is eighty.
    Niteteen is nineteen, ninety is ninety.
    Don't say 19 is ninety or 90 is nineteen.

参考答案：
“略”