24．A．a                         B．all                       C．the                        D．不填

23．A．with                    B．for                      C．from                      D．at

22．A．see                      B．visit                    C．look                             D．find

21．A．up                       B．over                    C．about                     D．than

20．A．their                    B．his                      C．its                         D．our

19．A．are                      B．is                        C．will be                   D．has been