A.F>F′
B.F<F′
C.F=F′
D.无法确定
答案:C
—Mum, could I have a MP3 like this?
—Certainly, we can buy _____ one, but as good as this. [ ]
A. a cheap
B. a cheapest
C. a cheaper
D. the cheapest
贫血最早出现的症状是()
A.吞咽困难
B.恶心呕吐
C.低热
D.晕厥
E.疲乏无力