{HEAD ~ The transformer} can, for example, be a power transformer, an audio frequency signal coupling transformer, or part of {TAIL ~ a filter circuit} where it may be that frequency variations or other causes can reduce the load presented by the output to the input to a value which adversely affects safety 
{ HEAD ~ The transformer } can , for example , be a power transformer , an audio frequency signal coupling transformer , or part of { TAIL ~ a filter circuit } where it may be that frequency variations or other causes can reduce the load presented by the output to the input to a value which adversely affects safety
HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH