Shopping on line can provide convenience and choice, but not websites are safe enough for shopping.
A. either; both
B. neither; any
C. both; both
D. both; all
网友回答
A. either; both
B. neither; any
C. both; both
(答案→)D. both; all
解析：第一空用both，构成 both...and ，用来连接两个宾语既方便，种类又多；第二空用all 与not连用，表示部分否定，并非所有的网站都安全，此处无两者之意。