1. Nowhere in nature is aluminum found free， owing to its always with other elements， most commonly with oxygen.
A. being combined B. having combined
C. to combine D. combined
2. Physics is the present day equivalent of used to be called natural philosophy， from most of present-day science arose.
A. which， what B. that， which C. what， which D. what， that
3. On no account ever leave the baby at home alone.
A. should you B. you should C. shall you D. you shall
4. the center of our planetary system was considered as heresy by the church in the Middle Ages.
A. It is the sun and not the earth is
B. That the sun and not the earth is
C. Being the sun and not the earth is
D. The sun and not the earth is
5. The reason that his property was confiscated by the country， it ， was that he was involve in a lot of fraudulent activities during the war.
A. was turned out B. was being turned out C. being turned out D. turned out
6. I'd rather you by train because the weather forecast said there would be heavy snow， tomorrow.
A. went B. should go C. will go D. go
7. Einstein won the Nobel Prize in 1921 and enjoyed great fame in Germany until the rise of Nazism he was expelled from Germany because he was a Jew.
A. when B. who C. then D. which
8. Nowhere but in the remotest region of the country find a place to settle down.
A. can he B. he can C. he D. for him to
9. With one leg broken in that car accident， he cannot even walk， run.
A. let alone B. that's to say C. not to speak D. not to mention
10. ， she led a life of complete seclusion.
A. Being disgraced B. Disgraced C. Disgracing D. She was disgraced
11. It to see so many children in that mountainous area cannot even afford elementary education.
A. pains her B. makes her pain C. is paining D. is pained
12. Our boss， Mr. Thompson， a raise in salary for ages， but nothing has happened yet.
A. was promising B. has been promising
C. promised D. has promised
13. A dream is to a person is wings are to a bird.
A. that B. which C. what D. as
14. The man sitting opposite me smiled dreamily， as if something pleasant in the past.
A. to remember B. remembered
C. having been remembered D. remembering
15. I him the Christmas gift by mail because he came home during the Christmas holidays.
A. ought to have sent B. couldn't have sent
C. must have sent D. needn't have sent