According to Ingrid Parkin, principal of the St. Vincent School for the Deaf in Johannesburg, people who know a few signs try to pass themselves off as interpreters. Those hiring them usually don’t sign, so they have no idea that the people they are hiring cannot do the job.
Source: http://www.foxnews.com/world/2013/12/12/interpreter-for-mandela-memorial-says-was-hallucinating/
naman knowledge 