A series of mischance happened. 一连串不幸的事情发生了 The student always asks his teacher a series of questions. 这个学生总是问他老师一连串的问题. He drew a series of parallel lines. 他画了一组平行线. Then began a series of experiments. 然后一系列的实验开始了. You don't need to a series of notes. 你不需要把一系列的笔记都写下来.
