【题目】_____you take an active part in physical activity _____be able to keep fit and stay healthy.
A. If only; you will B. If only; will you
C. Only if; you will D. Only if; will you
在线课程【答案】D
【解析】
试题分析：考查部分倒装。If only要是---，句子用虚拟语气；only +状语位于句子开头，句子用部分倒装。故选D。