9. 5 Write a , an , or – in front of the nouns. 1 ...... adult 2 ...... area 3 ...... MP3 player 4 ...... information 5 ...... CD 6 ...... escalator 7 ...... incident 8 ...... hare 9 ...... hour 10 ...... goods 11 ...... knowledge 12 ...... umbrella 13 ...... unit 14 ...... university 15 ...... yacht an an a – a an an a an – – an a a a