[单项选择]Some people viewed the findings with caution, noting that a cause-and-effect relationship between passive smoking and cancer remains （）.
A. to be shown
B. to have shown
C. to have been shown
D. being shown

[单项选择]Some people viewed the findings with caution, noting that a cause-effect relationship between smoking and cancer remains ______.
A. to be shown
B. to have shown
C. to have been shown D. being shown

[单项选择]Some people view the findings with caution, noting that a cause-and-effect relationship between passive smoking and cancer remains （　）.
A. to be shown
B. to have shown
C. to have been shown
D. being shown

[填空题]People do some shopping there.

[填空题]People do some cooking in it.

[单项选择] FAMILY BUSINESSES Many people at some stage in their lives consider setting up a business with their partner or other members of their family. The idea may seem very appealing, but the reality of working with someone close to you can often create unforeseen problem. 80% of family-run businesses think that when times get tough, love, romance or family bonds will see them through. But the fact is that although 70% of businesses are family run, only 40% of these companies survive into the second generation. Why do so many family businesses fail While money has traditionally been thought of as the root of all difficulties, the major problem is much more basic. In businesses which don’’t have family tie or relationships, people find it easier to communicate and to say what is on their mind. In contrast, with family businesses, people often make the mistake of thinking they know what views other family members have without actually discussing with them.
A. Because there would be abundant capital for operation
B. Because family bonds are helpful in overcoming difficulties
C. Because they hope to survive for generations
D. Because they can make profits without unforeseen problems.