Formation of new words with the help of prefixes

The meaning of a word in German can often be determined by knowing it's parts. We have already discussed on of the ways to form the new words in German - the suffix "chen":
http://deutschme.blogspot.de/2014/02/the-addition-of-suffixes-and-prefixes.html

New words can also be built with the help of different prefixes. Today we will learn two of them:

   Erz-"arch", "ultra" (argumentative intensiv)

• der Feind - der Erzfeind (arch-enemy)
• der Reaktionär - der Erzreaktionär (ultra-reactionary)

  Fehl-"false", "incorrect", "wrong", "bad" 

• der Start - der Fehlstart (false-start)
• die Diagnose - der Fehldiagnose (incorrect diagnosis)
• die Investition - die Fehlinvestition (bad investment)

Using German Vocabulary

 von Sarah M. B. Fagan