55．A．gatekeeper             B．seller                   C．waiter                    D．visitor

54．A．share                   B．take                     C．Pay                       D．have

53．A．until                    B．when                   C．unless                    D．since

52．A．everybody             B．nobody                C．somebody              D．none

51．A．shout                   B．explain                C．complain                D．speak

50．A．noisy                   B．quiet                   C．busy                      D．clean

49．A．right                   B．wrong                 C．important               D．polite

48．A．lively                         B．friendly               C．lucky                     D．polite

47．A．cause                   B．keep                    C．hear                       D．make

46．A．popular               B．difficult               C．important               D．enjoyable