21:

A new hair-growing drug is being sold for three times the price, per milligram, as the drug’s maker charges for another product with the same active ingredient.

A. as

B. than

C. that

D. of what

E. at which

Why the correct answer is C?

22:

From 1980 to 1989, total consumption of fish in the country of Jurania increased by 4.5 percent, and total consumption of poultry products there increased by 9.0 percent. During the same period, the population of Jurania increased by 6 percent, in part due to immigration to Jurania from other countries in the region.

If the statements above are true, which of the following must also be true on the basis of them?

A. During the 1980’s in Jurania, profits of wholesale distributors of poultry products increased at a greater rate than did profits of wholesale distributors of fish.

B. For people who immigrated to Jurania during the 1980’s, fish was less likely to be a major part of their diet than was poultry.

C. In 1989 Juranians consumed twice as much poultry as fish.

D. For a significant proportion of Jurania’s population, both fish and poultry products were a regular part of their diet during the 1980’s.

E. Per capita consumption of fish in Jurania was lower in 1989 than in 1980.

the answer key said B is the right answer but I think it should be E.

35:

Nitrogen dioxide is a pollutant emitted by automobiles. Catalytic converters, devices designed to reduce nitrogen dioxide emissions, have been required in all new cars in Donia since 1993, and as a result, nitrogen dioxide emissions have been significantly reduced throughout most of the country. Yet although the proportion of new cars in Donia’s capital city has always been comparatively high, nitrogen dioxide emissions there have showed only an insignificant decline since 1993.

Which of the following, if true, most helps to explain the insignificant decline in nitrogen dioxide emissions in Donia’s capital city?

A. More of the cars in Donia’s capital city were made before 1993 than after 1993.

B. The number of new cars sold per year in Donia has declined slightly since 1993.

C. Pollutants other than nitrogen dioxide that are emitted by automobiles have also been significantly reduced in Donia since 1993.

D. Many Donians who own cars made before 1993 have had catalytic converters installed in their cars.

E. Most car trips in Donia’s capital city are too short for the catalytic converter to reach its effective working temperature.

the answer key said E is the right answer but I think it should be D

38:

The market for recycled commodities like aluminum and other metals remain strong despite economic changes in the recycling industry.

A. commodities like aluminum and other metals remain

B. commodities like those of aluminum and other metals are remaining

C. commodities such as aluminum and other metals remains

D. commodities, such as aluminum and other metals, remain

E. commodities, like the commodities of aluminum and other metals, remains

I think the correct answer should be C instead of D.

21,争议题,集中在C,D之间, 个人倾向于D, 因为the price后面有插入语,of what更清晰.

22, 应该是E.

23, 答案没错是E,题意"Yet although the proportion of new cars "说的是new car,D的1993年以前的car装没装都不影响结论.

24, 争议集中在C,E之间,个人倾向于E,C中remains前面没有逗号是最大的问题. E没有明显错误,铝制的商品,也是讲的通的.

21 c charge the price for sth ,假如用what 指代什么？不是price ,别的没有了

22 e

23 e

24 c个人认为前后都没有逗号也是可以的 此题欢迎讨论。