I know I should on fat but knowing such things is not much help when it comes to shoppin

问题补充：

I know I should on fat, but knowing such things is not much help when it comes to shopping and eating.

A. cut up

B. cut in

C. cut down

D. cut off

答案：

A. cut up

B. cut in

(答案→)C. cut down

D. cut off

解析：动词短语辨析。A切碎；B插话；C砍到，削减；D切断；句意：我正当我应该减肥了，但是当涉及到购物和吃东西，知道这样的事情也就没有什么大的帮助了。