         jentence 1: The number of people: in. the  IK. infected: by | HIV._,- the.. virus ‘that  ‘auises Aids , increased: by almost 20 per  ant last year to nearly 50,000 .   Sentence 2; The global epidemic of HIV ;  [the virus that causes Aids., is tightening:  {§ grip. on Britain with a record number.   f new cases. diagnoséd last year .    