问题
选择题
Jane had just finished her homework ________ her mom asked her to practice playing the violin yesterday.
A．when
B．while
C．after
D．before
答案
答案：A
题目分析：考查连词：A. when当…时候，表示时间点，这时="at" this/that time，B. while当….时候，表示时间段，C. after在…后面，D. before 在….前面，句意：简刚刚完成作业这时妈妈叫她练习钢琴。选A。