Thomas Alva Edison didn’t “invent” the light bulb (灯泡), but rather he ______ a 50 –year –old idea, which is not well –known.

Can you describe _____it happened?— Yes,I was riding on my bike_____ a car knocked me down from behind[ ]

Mr.Smith an imprtant part when he gave the lecture last Friday .

I don’t mind telling you what I know.— You _______. I’m not asking you for it.

You haven’t been to the mountain, have you —_______.I’ll go there next week. It will be the first time for me.