Only when Mr Green lost his health, ________ realize how important it was．
Only when Mr Green lost his health, ________ realize how important it was．
A.does he
B.did he
C.has he
D.he did
答案及解析： B
Only when Mr Green lost his health, ________ realize how important it was．
A.does he
B.did he
C.has he
D.he did
答案及解析： B