Thanks for your help .
When I say These workers are of grades 2/7 I mean the skill level
In my country a worker who has just started work for a company , he will be classified as grade 01 . After a period of time he will be raised to grade 02 , and then grade 03 , 04....and grade 07 is the highest grade .Just as in the army when you first join the army you will be classified as private , and after 01 or 02 years you will be raised to the rank of private first class and so on ......The salary received will be commensurate with the grade a worker is classified . The higher grade the higher salary.
Please help me write grade 2/7 in words .eg. grades 2 out of seven or something like that.
By the way , please tell me other ways of expressing this idea.
Thanks and Best regards