Check out example codes for "c# add list to list". It will help you in understanding the concepts better.
Code Example 1
List<string> initialList = new List<string>();
// Put whatever you want in the initial list
List<string> listToAdd = new List<string>();
// Put whatever you want in the second list
initialList.AddRange(listToAdd);
Code Example 2
GlobalStrings.AddRange(localStrings);
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