get Data using Linq

Question

Hi

I have below data 

Group 2C

Group 2C(i)

Group 3C

Group 3D

Group 3D(i)

Group 3E

Group 3G

I want to display like below

Group 2C , Group 2C(i)

Group 3C

Group 3D , Group 3D(i)

Group 3E

Group 3G

Thanks