What do you think of when you see the word "actor"？Actors，many people would say，are the people who perform up on a stage（在舞臺(tái)上表演），on television or in films.They are all about being seen.However，there is a group of actors who are never seen.They are only heard---and just hardly at that.
   Meet loopers.Their job is to record what people in the background of a scene could be saying.The work begins only after the show or film has been shot and edited（編輯）.
   Once recent Sunday，on a sound stage at Fox Studios in Los Angeles，seven loopers were recording dialogues for a TV show，They were working on a restaurant scene，speaking lines（臺(tái)詞）that people at background tables might speak.As they recorded，the loopers stood in a circle under two overhead microphones（話筒）.A scene played silently on a big screen.At exactly the right moment，they started to walk around and talk，later，the dialogues would be mixed into the scene they were watching.
   David Betancount，a mixer explained why looping was necessary."The dialogues apper meaningless，but they improve the experience of what you are watching，"he said. "A show without these dialogues just feels dead. "
   To fill in the background sounds，looper s watch the movie or show，take notes and then discus how they should do their research.For example，when they were working on Bones，a cine show，the looper s researched the language of forensic（法醫(yī)的）scientists.
   The next time you watch a show or film，pay some attention to the background dialogues.Imagine what scene would be like without the loopers.You will then realize how important these "unseen actors" are.

（1）People can usually see

A

A

on TV or in films.
A．a(chǎn)ctors
B．loopers
C．mixers
D．editors
（2）According to the article，the loopers

B

B

.
A．can be seen on screen
B．record back ground dialogues
C．would perform on a stage
D．shoot and edit shows or films
（3）Paragraph 3 mainly explains

D

D

.
A．why looping is important
B．who records the lines
C．where looping is made
D．how looping is recorded
（4）We can learn from the article that

C

C

.
A．looping begins before a show is shot
B．looper s usually work in groups of seven
C．looping can make a show full of life
D．looper s watch the show after taking notes