单项选择题
Smoking is forbidden in the workshop, please stop it. Sorry, I（）
A.am not sure B.have no idea C.do know D.did not know
单项选择题 Smoking is bad for your health. So, please（）
单项选择题 Singing these songs, I could not help（）the good old days.
单项选择题 She was awarded the highest（）for his contribution to world peace
