单项选择题
Processed food and food （）contains chemicals and preservatives should be avoided.
A.when B.where C.which D.who
单项选择题 —Shall I use your dictionary? —（）
单项选择题 Tests provide grades, but they also let you know what you need to spend more time（）and they help make your new knowledge permanent.
单项选择题 The good service at the hotel（）the poor food to some extent
