You have waited 45 minutes for the valuable 10 minutes’ break between classes. But when the bell for the next class rings, you can’t   36   how quickly time has passed.
If you are familiar with this   37  , you’ll know how time flies when you are having fun-and  38   when you are bored. Now scientists have   39   a reason why this is the case.
Scans have shown that patterns of activity in the brain   40   according to how we focus on a task. When we are   41  , we concentrate more on how time is passing. And this makes our brains   42   the clock is ticking more slowly.
In an experiment   43   by a French laboratory, 12 volunteers watched an image   44  
researchers monitored their brain activity.
The volunteers were told to   45   concentrate on how long an image appeared for, then
46   the color of the image, and thirdly, study both duration and color. The results showed that  47   was more active when the volunteers paid   48   subjects.
It is thought that if the brain is   49   focusing on many aspects of a task, it has to  50  its resources, and pays less attention to the clock.  51 , time passes without us really   52   it, and seems to go quickly. If the brain is not so active, it concentrates its   53   energies on monitoring the passing of time.   54  , time seems to drag.
Next time you feel bored   55  , perhaps you should pay more attention to what the teacher is saying!
36．A．guess                      B．learn                      C．believe                   D．doubt
37．A．view                      B．point                      C．scene                      D．experience
38．A．drags                      B．stops                      C．backs                      D．gains
39．A．thought over           B．made up                 C．suggested                D．come up with
40．A．change                   B．develop                  C．grow                      D．slow
41．A．sleepy                    B．bored                            C．excited                   D．active
42．A．report                     B．think                      C．decide                    D．see
43．A．produced                B．carried                    C．tried                       D．performed
44．A．so                          B．when                      C．while                      D．but
45．A．partly                     B．quickly                   C．how                       D．first
46．A．remember               B．focus on                 C．forget                    D．tell apart
47．A．the researchers        B．the experiment        C．the clock                 D．the brain
48．A．much attention to                                       B．more attention to    
C．attention to many                                        D．attention to more
49．A．busy                       B．likely                            C．ready                      D．sure
50．A．focus                      B．gather                     C．reach                     D．spread
51．A．However                B．Furthermore            C．Therefore                D．Finally
52．A．recognizing             B．watching                 C．noticing                  D．counting
53．A．enough                   B．full                        C．right                       D．proper
54．A．In fact                    B．As a result                     C．For example            D．Instead
55．A．in class                   B．with work               C．in mind                  D．of lessons