Repeat every other character in string starting with second character Requirements:


Take a single word as input with only lowercase alphabetical characters (a-z)
Output a string where every other character is repeated, with the first repeated character being the second character in the string


Example:

Input: abcde

Output: abbcdde

Winning Criteria:
Standard code golf. Shortest number of bytes in program wins.

Clarification:
For languages with 1-based indexing the output must still match the above, aabccdee is not an acceptable solution.
sed, 12

s/.(.)/&amp;\1/g


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