大全 41 those问题

41.        According to a study published by Dr. Myrna Weissman, only one percent of Americans born before 1905 had suffered major depression by the age of seventy-five; of those born since 1955, six percent had become depressed by age twenty-four.

(A) only one percent of Americans born before 1905 had suffered major depression by the age of seventy-five; of those born since 1955, six percent had become depressed by age twenty-four

(B) only one percent of Americans born before 1905 suffer major depression by the age of seventy-five; if they are born since 1955, six percent become depressed by age twenty-four

(C) of Americans born before 1905, only one percent of them have suffered major depression by age seventy-five, but six percent of those born since 1955 do by the age of twenty-four

(D) major depression is suffered by the age of seventy-five by only one percent of Americans born before 1905, and by age twenty-four by the six percent born since 1955（A）

(E) Americans born before 1905 suffer major depression by the age of seventy-five only one percent of the time, but six percent of those born since 1955 did so by age twenty-four

those 不是不可以单独使用吗？

71.        Aging is a property of all animals that reach a fixed size at maturity, and the variations in life spans among different species are far greater as that among individuals from the same species: a fruit fly is ancient at 40 days, a mouse at 3 years, a horse at 30, a man at 100, and some tortoises at 150.

(A) among different species are far greater as that among individuals from

(B) among different species are far greater than that among individuals from

(C) among different species are far greater than those among individuals of

(D) between different species are far more than that between individuals of（C）

(E) between different species are greater by far than is that between individuals from

那这道题呢？

先行词？

variations　是复数

指代复数不用that 用those,

这题我也有问题呀。。这种题不太知道怎末分析的说。。。总觉得晕的慌