THE human face doesn't lie．We show sadness and happiness through our expressions．But exactly how many emotions can our face make？Scientists used to believe we had six basic facial expressions that tell others how we feel：sad，happy，surprised，fearful，angry and disgusted （恶心的）．

But a new study shows that our faces can do more than we think．Scientists from Ohio State University found out that humans can actually make 21different facial expressions after studying how people move their facial muscles．

The scientists took pictures of 230volunteers making faces in response to different cues （提示）．These cues included phrases like"you just got some great unexpected news"，which produced a"happily surprised"reaction from volunteers．Other cues included"you smell a bad odor （气味）"，which caused"disgusted"faces．

In total，around 5，000pictures were taken of the volunteers．The scientists then studied similarities of these pictures using a computer expression database．This helped them to define a facial expression．"That tells us that these 21emotions are expressed in the same way by nearly everyone，"said DrAleix Martinez to The Daily Telegraph．For example，to express surprise，92percent of volunteers widened （睁大） their eyes and opened their mouth．And 99percent raised their cheeks （脸颊） and smiled to show being happy．

We are not always aware of our facial expressions，which can hold clues to how we really feel．So these results may have a big impact （影响） on medical treatment．If doctors were able to recognize more complex （复杂的） emotions，it would help doctors treat patients suffering from certain diseases．

摘自http://paper．i21st．cn/story/93401．html

46．Scientists used to believe how many basic facial expressions that tell others how we feel？___

A.21

B.230

C.92．

D.6

47．How didscientists from Ohio State University find out the number of facial expre