When I try to understand __________ that prevents so many Americans from being as happy as
A. why it does
B. what it does
C. what it is
D. why it is
Christina Hudson is going to __________ in London.
A. do some business
B. know something about the McDonald clan
C. visit the castle and do some shopping
D. study the history of the city
Why did the natural pearl trade collapse in the 1930s？
A. Because of competition from cheaper Japanese pearl-fishing.
Because of competition from oil industry.
C. Because of competition from cheaper Japanese cultured pearls.
D. Because of pollution from oil industry.
The United States Constitution provides for a count of the population __________ a census,
A. called
B. which called
C. that it is called
D. as called
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