题目内容：

1.But that he saw it,he( )it.
A could not have believed B did not believe
C could not believe D can not believe
,从句是一般过去时,主句不应该是过去将来时吗?那这么选A呢?
2.He must have an accident ,or he ( )here then.
A should have been B should be
C would be D were
主句是过去将来时,那么从句应该是一般过去时或者过去将来时,怎么是A