问题
选择题
About ____of the students in Grade Nine this year were born in the_____.
A．three five; 1996.
B．three fifths; 1990s
C．third fifth; 1997.
D．third fifths; 1990s
答案
答案：B
分数的构成为分子用基数词，分母用序数词，分子如果大于1，则分母序数词一般都用复数形式，故用排除法只能选B项。