题目

Susan plays the piano very well, ________ she is only five years old.A.if B.though C.for D.since 答案：【答案】B【解析】句意：苏姗钢琴弹得很好，尽管她才只有五岁。考查连词辨析。if如果；though尽管；for后面加时间段，表示一段时间，是完成时态的标志；since自从，后面加时间点，是完成时态的标志。此处前一句的时态是一般现在时，所以排除C和D选项；根据语境可知此处需要用though来引导让步状语He asked them to come to his office one _________. A. at a time                B. at one time             C. at no time               D. at all times