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【单选题】
一元二次方程ax 2 +bx+c=0（a≠0，a，b，c都是有理数）的公式是x= -b± b 2 -4ac 2a （b 2 -4ac≥0）通过研究我们知道：若方程的根是有理数根，则b 2 -4ac必是完全平方数，已知方程x 2 -2x+m=0的根是有理数，则下列数中，m可以取的是（ ）A.
8
B.
4
C.
-2
D.
-3
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【单选题】Whenever the economic outlook is troublesome, the convention is for both men and women to wear more conservative clothes.
A.
每当经济前景不明朗时,无论男女,其着装都较为开放。
B.
每当经济前景不明朗时,无论男女,其着装都较为保守。
C.
每当经济前景向好时,无论男女,其着装都较为开放。
D.
每当经济前景向好时,无论男女,其着装都较为保守。
【单选题】In many Moslem countries, women have to______ in public.
A.
wear more clothes than men
B.
wear veils to hide their faces
C.
protect their faces from being hurt
D.
wear beautiful clothing
【单选题】下列哪项不是慢性阻塞性肺疾病康复治疗的作用机制？（）
A.
提高机体能量储备
B.
纠正病理性呼吸模式
C.
改善和促进痰液排出
D.
提高患者生活质量
E.
改善心理状况，缓解焦虑、抑郁、紧张、暴躁等心理障碍
【单选题】—We should do what we can ________ the endangered animals. —Yes, it’s our duty_________ them.
A.
save; to protect
B.
save; protect
C.
to save; protect
D.
to save; to protect
【判断题】When the economic outlook is troublesome, both men and women will wear more fashionable clothes.
A.
正确
B.
错误
【单选题】In women's wear the inspiration was _.
A.
the independent women
B.
the active,self-aware women
C.
the lovely women
D.
the kind,confident women
【单选题】---I think we should save the endangered animals. ---I agree ______ you. There aren’t many of them. [ ]
A.
so
B.
with
C.
that
D.
about
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