1 . Carbon dioxide emissions (排放) from the burning of energy sources ______ 80 percent of greenhouse gas emissions in the United States.

A．cut down

B．account for

C．add up

D．put on

2 . I’m quite sure my keys are in the house. If we just keep seeking, they will certainly ______.

A．turn up

B．take up

C．set off

D．put off

3 . The man who provided relevant information would be offered a(n) ______ of $5000 for the arrest of the murderer, according to the news on TV last night.

A．award

B．reward

C．prize

D．price

4 . Mothers love children, which is a(n) ______ fact in spite of cultural differences.

A．artificial

B．foolish

C．universal

D．amazing

5 . If you often ______ others, you may do everything successfully; if you stick stubbornly to your own view, you will get into trouble everywhere.

A．admire

B．affect

C．consult

D．combine

6 . It’s a(n) ______ in China that all the family members get together to have a big feast on the day before the Spring Festival to celebrate the harvest of the year.

A．custom

B．origin

C．religion

D．fashion

7 . It’s necessary that children ask for their parents’ ______ before going out from their homes.

A．devotion

B．protection

C．cooperation

D．permission

8 . It is said that the project will cost $580 million, half coming from investors, the rest ________.

A．to borrow

B．to be borrowed

C．borrowing

D．being borrowed

9 . According to our teacher, we should take detailed notes in class because they are more ________ than our memory.

A．active

B．reliable

C．honest

D．stubborn

10 . Cave exploration, which has come to be known in recent years, is a ________ new sport.

A．relatively

B．gradually

C．publicly

D．strictly