[求助]xdjm多多帮忙，天山15，18，19

ztlbox

15.   A substance from the licorice plant, 50 times sweeter than sucrose, was recently discovered, is not only a natural sweetener but also prevents tooth decay.

(A) A substance from the licorice plant, 50 times sweeter than sucrose, was recently discovered

(B) A substance, which was recently discovered, from the licorice plant, 50 times sweeter than sucrose,

(C) A substance from the licorice plant, which was recently discovered to be 50 times sweeter than sucrose,

(D) A substance from the licorice plant, 50 times sweeter than sucrose , which was recently discovered,（B）

(E) A recently discovered substance, 50 times sweeter than sucrose from the licorice plant,

我选E，错在哪里呢？

18.   Interest rates on mortgages have declined steadily during the first six months of this year but virtually remained unchanged during the next three months.

(A) have declined steadily during the first six months of this year but virtually remained unchanged

(B) declined steadily during the first six months of this year but virtually remain unchanged

(C) steadily declined during the first six months of this year but remain virtually unchanged

(D) declined steadily during the first six months of this but have remained virtually unchanging’（E）

(E) declined steadily during the first six months of this year but have remained virtually unchanged

彻底被这道题的时态搞晕掉了，前面现在时，后面完成时，是么道理呢？

19.   It could be argued that the most significant virtue of a popular democracy is not the right to 10 participate in the selection of leaders, but rather that it affirms our importance in the scheme of things.

(A) but rather that it affirms

(B) but rather its affirmation of

(C) but rather it’s affirmation in terms of

(D) but instead of that, its affirming that（B）

(E) affirming rather

B中的its指的是什么？virtue ，a popular democracy ，the right ？

怎么区分它到底指谁呢？

20.   uritan fanatics brought to civil and military affairs a coolness of judgment and mutability of purpose that some writers have though inconsistent with their religious zeal, but which was in fact a natural outgrowth of it.

(A) but which was in fact a natural outgrowth of it

(B) but which were in fact a natural outgrowth of it

(C) but which were in fact natural outgrowths of it

(D) but it was in fact a natural outgrowth of them（C）

(E) which was in fact a natural outgrowth of it

but which were in fact a natural outgrowth of it 什么意思呀。

rt316

以下是引用ztlbox在2004-7-31 6:30:00的发言：

15.   A substance from the licorice plant, 50 times sweeter than sucrose, was recently discovered, is not only a natural sweetener but also prevents tooth decay.

(A) A substance from the licorice plant, 50 times sweeter than sucrose, was recently discovered

(B) A substance, which was recently discovered, from the licorice plant, 50 times sweeter than sucrose,

(E) A recently discovered substance, 50 times sweeter than sucrose from the licorice plant,

我选E，错在哪里呢？E change the meaning of the sentence, you can find the difference of the green highlight.

18.   Interest rates on mortgages have declined steadily during the first six months of this year but virtually remained unchanged during the next three months.

(A) have declined steadily during the first six months of this year but virtually remained unchanged

(B) declined steadily during the first six months of this year but virtually remain unchanged

(C) steadily declined during the first six months of this year but remain virtually unchanged

(D) declined steadily during the first six months of this but have remained virtually unchanging’（E）

(E) declined steadily during the first six months of this year but have remained virtually unchanged

彻底被这道题的时态搞晕掉了，前面现在时it means that the action was finished in the past，后面完成时it means that the action began in the past, has been active till now，是么道理呢？

19.   It could be argued that the most significant virtue of a popular democracy is not the right to 10 participate in the selection of leaders, but rather that it affirms our importance in the scheme of things.

(A) but rather that it affirms

(B) but rather its affirmation of

(C) but rather it’s affirmation in terms of

(D) but instead of that, its affirming that（B）

(E) affirming rather

B中的its指的是什么？virtue ，a popular democracy ，the right ？

怎么区分它到底指谁呢？sometime, we can use A's B to refer to B of A

20.   uritan fanatics brought to civil and military affairs a coolness of judgment and mutability of purpose that some writers have though inconsistent with their religious zeal, but which was in fact a natural outgrowth of it.

(A) but which was in fact a natural outgrowth of it

(B) but which were in fact a natural outgrowth of it

(C) but which were in fact natural outgrowths of it

(D) but it was in fact a natural outgrowth of them（C）

(E) which was in fact a natural outgrowth of it

but which were in fact a natural outgrowth of it 什么意思呀。I think 'which' refers to 'a coolness of judgment and mutability of purpose'

ztlbox

thank you