问答题
The food we eat seems to have profound affects on our health. 【M1】______Though science made enormous steps in making food fitter to eat, 【M2】______it has, at the same time, made many foods unfit to eat. Some researchhas shown that perhaps 80 percent of all human illnesses is related 【M3】______to diet and 40 percent of cancer is related to diet as well, especially cancer of the colon. Different cultures are more proneto contract certain illness because the food that is characteristic in 【M4】______these cultures. Which food is related to illness is not a new discovery. 【M5】______In 1945 , government researchers realized that nitrates and nitrites, commonly used to preserve color in meats, and other foodadditives, causing cancer. Yet, these carcinogenic additives remain 【M6】______in our food, and it becomes more difficult all the time knowing which 【M7】______things on the packaging labels of processed food are helpful or harmful. The additives which we eat are not all so direct. Farmers often give penicillin to beef and poultry, and because of this, penicillin has beenfound in the milk of treating cows. Sometimes similar drugs are 【M8】______administered to animals not for medical purposes, but for financialreasons. The farmers are simply trying to fat the animals in order to 【M9】______obtain a higher price on the market. Although the Food and DrugAdministration has tried repeated to control these procedures, 【M10】______the practices continue.
【答案解析】解析：句意：某研究表明人类80％的疾病与饮食相关。宾语从句主语“80 percent of all humanillnesses”的中心词“illnesses”为复数形式，根据主谓一致的原则，谓语动词应同样采取复数形式，应将is改为are。
问答题
【M4】
【正确答案】正确答案：because∧一of
【答案解析】解析：句意：不同文化的人们往往会因这些文化所特有的某种食物而染上某种特定的疾病。because“因为”为表示因果关系的连词，其后应该跟句子，但分析本句结构可知，“that is characteristic inthese cultures”为定语从句修饰先行词“the food”，故本句中心词仅仅是名词“the food”，所以应将because改为because of才符合语法。
问答题
【M5】
【正确答案】正确答案：Which—That
【答案解析】解析：句意：食物与疾病相关，这事并不新鲜。结合句意并分析句子结构可知，“food is relatedto illness”应该处理为主语从句，此从句中不缺任何成分，只能用that引导。
问答题
【M6】
【正确答案】正确答案：causing一caused
【答案解析】解析：句意：1945年政府研究者发现，常用于肉类颜色保鲜的硝酸盐和亚硝酸盐以及其他食物添加剂会致癌。分析句子结构可知，“nitrates and nitrites，and other food additives”为动词“realize”宾语从句的主语，而cause则为宾语从句的谓语，不可采用非谓语动词形式，结合上下文时态，应改为caused。
问答题
【M7】
【正确答案】正确答案：knowing一to know
【答案解析】解析：句意：我们很难辨别加工食物包装标签上所列出的添加剂之中哪一个有益哪一个有害。本句为it作形式主语引导的“it is(becomes)difficult(for sb．)to do sth．”结构，表示“做某事对(某人)来说是困难的”，其中真正主语应该由不定式形式引出，应改为to know。