完形填空。
There are robots all around us. Some do very1jobs like flying airplanes and driving subway trains.
And some do jobs.
When an automatic washing machine2 , water goes in. The machine waits until the water is hot3
washing the clothes. It does this by 'feedback' (反馈). Information about what's4is 'fed back' into
the robot to tell it5next.
Our eyes, ears and other senses (感官) are6feedback. They tell us7round us. So robots are
like people in8ways. They work and they have feedback.
But9robots look like people. Many are10ways. Robots control (控制) the temperature of our
houses, our cookers, our hot water systems. We can11the controls to the temperature we want. The
robot does12 . Its feedback usually come13thermostat (自动调温器).
Our kind of thermostat is a strip of metal (金属条), which bends (弯曲) when it gets hot. At the right
temperature, it bends just enough14a switch. This turns off the heat. As the air around it gets15 ,
the metal gets straight, and this turns the heat on again.

( )1. A. easy
()2. A. is switched on
()3. A. after
()4. A. happening
( )5. A. how to do
( )6. A. we
()7. A. what will happen
( )8. A. some
( )9. A. many
( )10. A. hide
( )11. A.set
()12. A. something
()13. A.up
()14. A. to work
()15. A. cold

B.
B. is switched
B. before
B. happens
B. what to do
B. our
B. what’s happening
B. any
B. a lot of
B. to hide
B. setting
B. something other things
B. to
B. working
B. hot

C. different
C. is switching
C. as soon as
C. to happen
C. what to do it
C. us
C. to happen what
C. two
C. very few
C. hidden
C. to set
C. half the work
C. from
C. to working
C. cool

D. difficult
D. switches on
D. while
D. happened
D. to do what
D. they
D. something will happen
D. three
D. a little
D. hiding
D. sets
D. the rest
D. in
D. works
D. warm