No matter how frequently __________, the works of Beethoven still attract people all over the world.
| A.performed | B.performing |
| C.to be performed | D.being performed |
. The missing boys were last seen _______ near the river.
| A.playing | B.to be playing | C.play | D.to play |
. The patient was warned _______ oily food after the operation.
| A.to eat not | B.eating not | C.not to eat | D.not eating |
. I regret _______ you that we are unable to offer you employment.
| A.informing | B.having informed | C.to inform | D.to informing |
. You had better get a doctor _______ your bad tooth.
| A.pull out | B.to pull out | C.pulled out | D.pulling out |
. The matter had better _______ as it is.
| A.leave | B.being left | C.leaving | D.be left |