Task: Text Simplification
Input (English): they would later return to the revived series in the 2008 christmas special " the next doctor " , introducing two new variants of the race ; the cyber-shades and the cyber-king.
Output (English): they would later come back to the became again number , order , group , line in the 2008 christmas special " the the one after expert " , putting into use for first time two new things changed of the group of the same blood ; the cyber-shades and the cyber-ki.