It is Yale's course selection period during the first two weeks of classes which allows you to participate in courses that interest you without enrolling in them right away.

所谓的“选课 试听阶段”指的是新学期伊始前两周的试听课阶段，这时你可以选择去试听自己感兴 趣的课程，而不用马上做出决定最终是否选修这门课程。

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Siddique had been fascinated by computers from his early teens, eventually enrolling in a computing technician's course at the Central College of Commerce in Glasgow.

BBC: NEWS | UK | Scotland | The quiet student plotting terror