Combining array elements

Question

I want to combine 2 consecutive elements of the even str array to create another string array with output as shown in example

 

For example if we have 6 elements in an array like

string[] str = new string[] {"a", "b", "c", "d", "e", "1"}

it will combine in another string array strCombined to show output of {"ab", "cd", "e1"}

 

Please advise on how this can be done?