Thomas Alva Edison didn’t “invent” the light bulb (灯泡), but rather he ______ a 50 –year –old idea, which is not well –known.
She brought with her three friends, none of I had ever met before.
We wonder ___________ quite a number of living things are dying out.
He was so busy that he couldn’t help ____________ the experiment.
After he ________ the golf club, he has ________ a number of competitions.
My uncle’s house is much smaller than ours, but it is twice expensive.