Juan loved winter more than any other season. He wasn’t sure   26  , but sometimes he thought about it.   27  it was that cold feeling he had, on a snowy night, looking out at the blowing, falling snow, safe and   28   inside with his family. Or maybe it was   29   those mornings when he could play in the snow with his friends. Christmas, his favorite festival anyway, was always even more   30   when the whole world was white.

  Upstate New York was a(n)   31   place to live in. The summer was warm and green. Autumn was a rainbow(彩虹) of colorful leaves.   32   would arrive in a few months and all would be well in Juan’s world.

  One day, Juan’s grandfather said excitedly, “We are   33   to Florida! No more cold, no more snow or ice, and no more winter!”

  Grandmother Marie was also very   34  . She hugged Juan. “Aren’t you excited, Juan?” she asked, trying not to notice his expression.

  “I don’t want to go there at all. I   35   to live here.” Juan cried.

26 A. when            B. where          C. why

27 A. Perhaps          B. Instead         C. Finally

28A. stupid            B. alone          C. comfortable

29 A. because          B. because of       C. instead of

30 A. special           B. boring          C. silly

31 A. awful            B. great           C. dangerous

32 A. Winter           B. Spring          C. Money

33 A. connecting        B. remaining       C. moving

34 A. sad              B. happy          C. worried

35 A. prefer            B. reject          C. agree

胎儿与母体进行物质交换的结构是（　　）