________ the earth to be flat, many feared that Columbus would fall off the edge of the earth.
A．Having believed B．Believing
C．Believed D．To believe
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
________ away from school for two weeks, I have quite a few lessons to catch up with.
A．Having been B．To be
C．Been D．Being
The landslide occurred at midnight, killing five people and ________ seven others ________.
A．leaving；injured B．leaving；injuring
C．left；injured D．left；injuring
________ by reporters about the case, Mr. Sun said Chongqing takes a clearcut attitude and is taking resolute measures.
A．Having asked B．To be asked
C．Asking D．Asked
Life is like riding a bicycle. ________ your balance, you must keep moving.
A．Keeping B．To keep
C．Keep D．Having kept
