【简介】感谢网友“雕龙文库”参与投稿，这里小编给大家分享一些，方便大家学习。
49.Whether you live to eat or eat to live, food is a major _______ in every familys budget.
A.nutrition
B.expenditure 花费 费用
C.routine 例行公事 常规
D.provision 供应量
50.Now a paper in Science argues that organic chemicals in the rock come mostly from __________ on earth rather than bacteria on Mars
A.configuration 结构 分布形状
B.constitution 宪法 事物的一般结构
C.condemnation 批评 责难
D.contamination 化学污染 放射性污染
51.There is much I enjoy about the changing seasons, but my favorite time is the ________ from fall to winter.
A.transmission
B.transformation 转变
C.transition
D.transfer
