化学t n是什么:有关现在分词的单选

来源:百度文库 编辑:神马品牌网 时间:2024/05/02 07:53:56
______from heart trouble for years,Professor White has to take some medicine with him wherever he goes.
A.Suffered B.Suffering C.Having suffered D.Being suffered

这道题我选的是B,可是错了,请大家解释一下并给出准确的答案.谢谢.

C
for years用完成时