Johnson, to grasp the chance to bee a doctor, decided to take up teaching.
A. fails
B. failed
C. to fail
D. having failed
网友回答
A. fails
B. failed
C. to fail
(答案→)D. having failed
解析：考查现在分词的完成式做状语：句意：Johnson没能抓住机会成为医生，他决定从事教学。两个逗号中间是插入语，实际上是状语，因为Johnson先没有抓住机会，然后才决定从事教学的，所以状语的动作在句子的动作前面发生，用现在分词的完成式，选D。