31.A.make B.cause C.leave D.prove
30.A.example B.copy C.model D.sample
29.A.spends B.lasts C.consumes D.takes
28.A.on B.for C.in D.with
27.A.which B.whose C.its D.what
26.A.best B.most C.proper D.reasonable
25.A.convince B.examine C.accept D.think
24.A.single B.simple C.easy D.similar
23.A.to B.on C.up D.in
22.A.raise B.remain C.save D.preserve