【题目】To keep healthy, Professor Johnson ______ cycling as a regular form of exercise after he retired.
A. carried out B. caught on C. took up D. made for
在线课程【答案】C
【解析】试题分析:为了健康，Johnson教授在退休之后开始把骑单车作为一种锻炼方式。根据句意可知，take up：开始从事，开始做，故选C。 carry out：实施；carry on：进行; make for:弥补。