explanation    A. excellent           B. excuse        C. explain          D. express

biology               A. commercial      B. observe    C. occur            D. obvious

 chief                   A. believe              B. lie             C. tie                 D. diet

worthy               A. thread               B. further          C. worth             D. through

chapter                  A. chorus                  B. stomach             C. chain             D. Christmas

Black children used to go to  __________ （单独的）schools.

Copacabana has just celebrated its one ___________ （百年） birthday.

He used the __________ （最新的）ideas and technical inventions of his day in his books.

Try to use traveler’s cheques if possible and avoid ________ （携带） too much money.

My parents’ ______________（鼓励） has made me more confident in my future.