问题
选择题
To keep healthy, Professor Johnson ______ cycling as a regular form of exercise after he retired.
A．took up
B．caught on
C．carried out
D．made for
答案
答案：A
句意为：为了保持健康，Professor Johnson 退休后开始骑自行车来作为一种定期的锻炼形式。take up 开始工作，从事某项活动，所以选A 。