Question

【题目】Exercise is the key ______ your health．

A.to improveB.to improvingC.in improvingD.of improving

Answer 1

【答案】B

【解析】

考查固定短语。句意：锻炼是改善你健康的关键。此处考查短语the key to doing sth做……的关键，to是介词，其后接动名词，故选B项。