String variable for age groups

Dear Statalisters,

I am using Stata 13.1 and I am trying to convert a variable for age groups in the form 1- ; 6- ; 11- , obtained after converting a continuous age variable (1-100) using the following command:
into a string variable with specific age intervals that look like this 1-5 ; 6-10 ; 11-15 ; ...

Any help will be appreciated.

Thanks.