_____several times the young scientist still kept on making his experi-ments.
   A.Having been failed      B.Having failed
   C.Though failed          D.Because of failure

I know it’s not important,but I can’t help_____about it.
   A.to think    B.and think    C.thinking    D.being thought

He felt a stone____his back.
　 A.hitting 　 B.hit 　 C.hitted D.to hit

——What do you suppose made her worried? ——_____a gold ring.
   A.Lose     B.Lost    C.Losing     D.Because of losing

The stranger you saw_____with a big travelling-bag stayed in Room 104 yesterday.
   A.to come in     B.come in    C.has come in   D.who came in

She made a candle_____us light.   A.give     B.gave   C.to give   D.given

____,your composition is full of mistakes.
   A.Writing carelessly           B.Written carelessly
   C.Having written carelessly     D.Being written carelessly

The policeman put down the phone,____with a smile on his face.
  A.satisfied     B.satisfying    C.to be satisfied    D.having satisfied

At the shopping-centre,he didn’t know what____and____with an empty bag.
  A.to buy;leave       B.to be bought
  C.to buy;left         D.was so buy;leave

The headmaster wanted the new classroom building___as soon as pos-sible.
  A.to put up               B.to be put up
  C.to have been put up      D.being put up