[求助]补充113 all&some的逻辑关系

雪落无声

113.a family is a household containing a householder and at least one person related to the householder.except for the homelss and people in group living quaters ,most people live in households.



according to the definition above ,which of the followeing must be true?


it isn't difficult to choose B,all families inculde a householder


but ,how about E,some homeless people reside in group living quarters.    it can be infered    from the above information that "    all homeless    people reside in group living quaters"so, some of the homeless     reside in group living quarters.


All people怎么样--》some people 怎么样，反之不然。这样的逻辑关系是成立的吧，那么E为什么错？

[此贴子已经被作者于2004-3-5 23:13:42编辑过]

weiyu

雪落无声MM,     原文好像没有"    all homeless    people reside in group living quaters"。the homeless and people in group living quaters是两种人

雪落无声

HUHU，怎么看走眼了？FT~


但是后面的问题还是有价值的，


All people怎么样--》some people 怎么样，some people怎么样推不出all people怎么样。这样的逻辑关系对吗？确认一下

weiyu

I think that it is right.

cranberry

记住must 和possible是不同的