还原染料隐色体主要是通过（）固着在纤维素纤维上。
A.离子键
B.共价键
C.氢键
D.范德华力
参考答案：A
妊娠期高血压疾病病人，解痉首选的凝物是（）
A.硫酸镁
B.巴比妥
C.冬眠1号
D.葡萄糖酸钙
E.硝苯地平
--- By the way, how much _______ the glasses?
--- The glasses? Oh, _______ 230yuan. [ ]
A．is, it's
B．are, they're
C．are, it's
D．is, they're
