（）需要用去垢剂或有机溶剂从生物膜上分离下来
A.外周蛋白
B.嵌入蛋白
C.共价结合的糖类
D.膜脂的脂肪酸部分
参考答案：B
“Do you regret paying five hundred dollars for the painting?”“No, I would gladly have paid______for it.”
A．twice so much
B．twice as much
C．as much twice
D．so much twice
用西餐时若需要暂时离开，应将餐巾折好（ ）。
A．放在椅子上
B．放在桌子上
C．放在盘子旁边
D．随手带走
