For a decade, that scientist has studied centenarians, looking for genes that contribute to longevity.
A. people who live to be 100 or older
B.people who are vegetarians
C.people who want to be fruitarians
D.people who are extraordinary

The man saw a notice __________to the door by a knife.
A.pin
B.pinned                               
C.pinning                             
D.having pinned

I'm expecting to have this book__________soon this year.          
A.published                  
B.publishing                       
C.to publish                     
D.publish

He was late because his alarm clock didn't __________that morning.
A.go off                 
B.ring out                             
C.break off                           
D.come out

The company was__________because of a shortage of orders.
A.solved                     
B.resolved                 
C.dissolved                          
D. involved

A.effect           
B.event             
C.emerge              
D.even

Choose the best answer A, B, C or D for each sentence
The mansion is set in 90 acres of beautiful, unspoilt _______.
A.country
B.countryman
C.countryside
D.countrywide

Choose the best answer A, B, C or D for each sentence
We were woken early by the sound of the birds _______.
A.song
B.sing
C.singer
D.singing

Select the antonym of the following bold and underlined word in each sentence in the unit
When combined with words in a song, it is one of the most powerful means of communication that humans have.
A.unconvincing
B.feeble
C.ugly
D.harmless

Some predictions by early science fiction writers about the future of electronic communication have turned to be extraordinarily accurate.
A.predictions 
B.science fiction
C.have turned
D.extraordinarily accurate.